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Office of the Superintending Engineer, I&CADD., Sripada Yellampally Project Circle, Mancherial, Adilabad Dist. Corrigendum No.6/2007- 08 of Package- 8 Dt: 28-05-2008 Name of Work : PRANAHITA-CHEVELLA LIFT IRRIGATION SCHEME – LINK- II - PACKAGE- 8–Detailed Investigation , Designs and Execution of Lift Irrigation Scheme for drawl and lifting of 114.24 TMC of water from Ragampet (V),near Kakatiya Canal, Choppadandi (M), Karimnagar District to Motevagu Reservoir and Carrying by a Gravity Canal to existing Flood Flow Canal to feed Mid Manair Reservoir with the Components such as Lined Gravity Canal, CM & CD Works, Lift, Pressure mains and Lined Tunnels with all associated Civil, Hydro-Mechanical and Electro- Mechanical works. Replies to pre-bid queries and other corrections in bid document Ref: Tender Notice No.15/2007-2008 Date: 22.03.2008 1.Querries of Maytas Hyderabad, Dt: 05-05-2008 and Replies. Sl. Clauses Reference Clarification Sought Reply No. ( Tender document) 1 Vol-Clause20.0(i)Part- Statements 1 pertaining to Organizational & to Bidders No change in clause. to 6 are not available in the Bid I: Eligibility & document. We presume that it is a Typing Information/ Data pertaining Technical Stage mistake. to Bidders Organization and Managerial Capability, Financial Capability and Technical Capabilities are available in Format B2, FormatB6 and Format B8.of Vol I, Part – B-Formats. Corrigendum being issued 2 Vol-I-Clause We presuming that the department will No change in clause. 101.0Labour Camp provide land for contractors labor and staff Bid condition holds good. and Contractor’ Staff colonies. Is it free or on chargeable basis. The Land required for Colony. Please Clarify providing amenities will be given free of cost from Government lands if available, otherwise the Contractor shall have to make his own arrangements . 3 Vol-I,Appendix- OS- We request the department to elaborate the No change in clause. Other Special scope of work, where the plants are Bid condition holds good and Conditions – Special proposed to be planted is self explanatory. Conditions of Contract,Clause No.33. 4 Vol-I,Part-E,Project As we observed at site there is neither Out of 146.24 TMC of water Profile- Scope of existing storage reservoir and nor provision drawn from Medaram Work,Sl No 1 & 4 in Package 7& 8.We request the authorities Reservoir, 32 TMC of water to specify the source from which water is to is being lifted and dropped in be drawn and location of reach starting to Kakatiya Canal in Package- point. 7. Balance 114.24 TMC of water is to be carried from Ragampet (V) towards Mothe Vagu Reservoir by continuing the tunnels of Package – 7. Othe 2. Other Corrections to Bid Document S.No. Clause FOR READ Reference 1 EMD/Bid Where ever “EMD Rs. 10.00 Crores EMD Rs. 30.00 Crores Security (Rupees Ten Crores)” (Rupees Thirty Crores) 2 Vol-I-NIT- PRANAHITA-CHEVELLA LIFT PRANAHITA-CHEVELLA LIFT Clause 30- IRRIGATION SCHEME – Link- IRRIGATION SCHEME – LINK- II Scope of II- Package - 8 - Detailed - PACKAGE- 8–Detailed Investigation , Designs and work, Part- Investigation , Designs and Execution of Lift Irrigation D- Basic Execution of Lift Irrigation Scheme for drawl and lifting Project Scheme for drawl and lifting of of 114.24 TMC of water Parameter 136.24 TMC of water from from Ragampet (V),near s-Clause- Ragampet (V),near Kakatiya Kakatiya Canal, Choppadandi 2.0- Scope Canal, Choppadandi (M), (M), Karimnagar District to of Work of Karimnagar District to Motevagu Motevagu Reservoir and this Reservoir and Linking of existing Carrying by a Gravity Canal Package, Flood Flow Canal to feed Mid to existing Flood Flow Canal Part – E – Manair Reservoir with the to feed Mid Manair Reservoir with the Components such as Project Components such as Profile – Scope of Work and wherever “ 1) Drawl of 114.24 TMC of 1) Drawl of 136.24 TMC of water from Ragampet (v) Scope of water from Ragampet (v) near Work “ is near Kakatiya Canal in 90 Kakatiya Canal in 90 days to days to drop in Motevagu referred drop in Motevagu Reservoir duly Reservoir duly linking of linking of existing Flood Flow existing Flood Flow Canal Canal to feed Mid Manair to feed Mid Manair Reservoir. Reservoir. 2) Excavation of Tunnels of 2) Approach channel from about 5.0 KM (Approx), Ragampet (v) near Kakatiya Surge pool, Adits, Canal for required discharge and Rockledge and Draft tube length. tunnels for required discharge and length. 3) Lining to Tunnel as per BIS Standards. 4) Lifting of 114.24 TMC of water in 90 days with 3) Construction of Intake static head of 109.10 M Structures, Off Structures and (Approx) in Single Stage Head Regulator. from Ragampet (V) near Kakatiya Canal. 4) Excavation of Gravity Open Stage 1: Channel including Formation of Total Discharge =419 Cumecs Embankments for required Total Power in discharge and length MW=722(approx.) 5) Lining to Canal No.of Pumps =Not more than 6) Construction of necessary CM 10 . & CD works Discharge per pump in 7) Tunnel, Surge pool, Adits, Cumecs=41.90 Rockledge and Draft tube tunnels Static Head in Meters= 109.10 for required discharge and length Power/Motor in MW=72.20 8) Lining to Tunnel 5) The Lift System has the 9) Lift following Components. 10) Lifting of 136.24 TMC of a) Approach water in 90 days with channel. required static head b) Pump House. 11) The lift system has the c) Electro- following components. Mechanical a) Approach channel. works. b) Pump House. d) Hydro- Mechanical c) Electro-Mechanical works. works. e) Surge d) Hydro-Mechanical protection works. f) SCADA System e) Surge protection g) Staff Quarters 12) Pressure mains to carry the for O & M required discharge for required length of about 1 h) Storage Shed Km 5) Pressure mains to carry 13) Delivery Cisterns. the required discharge for required length . With all associate Civil, Hydro-Mechanical and Electro- 6) Delivery Cistern of Mechanical works. suitable size and capacity. 14.Fabrication, Supply, 7) Excavation of Gravity inspection and testing, Open Channel up to Mothe Transportation, Storage, Vagu Reservoir including erection and Commissioning Formationof Embankments of Hydro-Mechanical to carry 114.24 TMC of Equipment such as portals at water in 90 days for a tunnel entrance and exit, length of about 4.25 KM draft tube gates, gantry (Approx). crane, trash rack and other 8) Lining to Gravity Canal associated civil works as per BIS Standards. connected with the lift scheme. 9) Construction of necessary CM & CD works 15.Fabrication, supply, inspection and testing, Transportation, 10) Construction of Intake storage, erection and Structures, Off take commissioning of Electro- Structures and Head Mechanical Equipment such Regulator. as pumps, pump auxiliaries 11) Lead Channel from motors, motor auxiliaries, Mothe Vagu Reservoir to station auxiliaries like lift, EOT Existing Flood Flow Canal. Crane, MOT Crane, DG Set, lighting system, Air 12) Lining to Lead Channel conditioning, Ventilation fire as per BIS Standards. fighting system and other Construction of necessary associated civil works with the CM & CD works. lift schemes. 14) Fabrication, Supply, 16.Fabrication, Supply, Erection, inspection and testing, Testing and Commissioning of Transportation, 220/11 KV Sub-Stations Storage, erection and with associated items like Commissioning of breakers, current Hydro-Mechanical transformers, Potential Equipment such as transformers, capacity voltage portals at tunnel transformers, isolators, entrance and exit, lighting arresters, all draft tube gates, structures and stringing of gantry crane, trash bus, earthing and all other rack and other miscellaneous works associated civil works connected with 220/11 KV connected with the lift sub-station under technical scheme. supervision and certification of A.P Transco. 15) Fabrication, supply, inspection and testing, 17.It shall be ensured that the Transportation, combined efficiency of motor storage, erection and and pumps should be not commissioning of less than 89 %. Electro-Mechanical Equipment such as 18. Operation and pumps, pump Maintenance of civil works auxiliaries motors, shall be for a period of 5 motor auxiliaries, (five) years, and for electro- station auxiliaries like mechanical and hydro- lift, EOT Crane, MOT mechanical works shall be for Crane, DG Set, lighting a period of 15 (Fifteen) system, Air years from the date of conditioning, completion certificate issued Ventilation fire fighting after successful completion of system and other the scheme. associated civil works Miscellaneous items: with the lift schemes. 1. Preparation of land plan 16) It shall be ensured that schedules & Land Acquisition the combined efficiency proposals on the basis of of motor and pumps approved alignment of Pipe line should be not less and allied works including than 89 %. submergence of balancing 17) Operation and Reservoir. Maintenance of Civil works 2. Preparation of cost estimates shall be for a period of Five (5) for all the components after years and for Electro- approval of designs and clubbing Mechanical and Hydro- the items suitably for record Mechanical works shall be for measurement purpose. a period of Fifteen (15) years from the date of completion 3. Formation of service roads in certificate issued after the project area. successful completion of the 4. All necessary scheme. permissions/clearances/ The bidder shall maintain the approvals are to be processed Civil works for five years. and obtained by the firm only on ( 3 years after defect liability its own costs. As a user agency period) and Electro- this department will initiate the Mechanical works for 15 years proposals in respect of this (13 years after defect liability scheme. period) with the cost quoted by him separately in the financial 5. Providing internal bid and no extra payments will electrification and lighting be made for men, material and arrangements, beautification machinery what so ever during and plantation near pump this period. He shall maintain house and intake well. this scheme with all standards and specifications of 6. Providing drinking water maintenance (conforming to regulating arrangements (Off- relevant BIS Codes of Take Sluice) to enroute practice) like, efficiency of villages. pumps and motors, regular servicing to Hydro and Electro- Mechanical items, carrying out 7. Design and preparation of repairs/replacements for engineering drawings for trouble free operation, civil erection of hydro mechanical maintenance like distempering works i.e., pumps, motors, to superstructure, painting to Pressure mains etc., doors and windows, repair / replacements of AC sheets/ridge pieces of 8. Plantation along the gravity godowns, maintenance of road ways and passages, up-keep canals, Pipe line, Pump of pump house area, houses, and land scaping beautification and plantation, around pump houses. maintenance of lawns and fountains etc. The bidder shall quote this item separately in financial bid and a separate agreement will be concluded for the same Miscellaneous items: 1. Preparation of land plan schedules & Land Acquisition proposals on the basis of approved alignment of Pipe line and allied works including submergence of balancing Reservoir. 2. Preparation of cost estimates for all the components after approval of designs and clubbing the items suitably for record measurement purpose. 3. Formation of service roads in the project area. 4. All necessary permissions/clearances/ approvals are to be processed and obtained by the firm only on its own costs. As a user agency this department will initiate the proposals in respect of this scheme. 5.Providing internal electrification and lighting arrangements, beautification and plantation near pump house and intake well. 6.Providing drinking water regulating arrangements (Off-Take Sluice) to enroute villages. 7.Design and preparation of engineering drawings for erection of hydro mechanical works i.e., pumps, motors, Pressure mains etc., 8.Plantation along the gravity canals, Pipe line, Pump houses, and land scaping around pump houses. As above Wherever Scope of Work – is Referred in Bid Documents Vol – I & II. 3 Vol-I-NIT- Where ever, “Fabrication, Supply, Deleted. Clause-30- Erection, Testing and Commissioning Scope of of 220/11 KV Sub-Stations with work-S.No-16 associated items like breakers, current transformers, Potential Substations transformers, capacity voltage transformers, isolators, lighting arresters, all structures and stringing of bus, earthing and all other miscellaneous works connected with 220 KV sub-station under technical supervision and certification of A.P Transco”. 4 Vol-1-NIT- The successful Bidder should The successful Bidder should Clause-31- however pay the EMD calculated @ however pay the EMD Special 2.5% of bid amount at the time of calculated @ 2.5% of bid conditions- signing the contract in the shape of amount at the time of signing Sl.No.14. demand draft or unconditional and the contract in the shape of irrevocable Bank Guarantee on the demand draft or unconditional standard format enclosed to the Bid and irrevocable Bank schedule for a total period not less Guarantee on the standard than the stipulated period of the format enclosed to the Bid completion of the work in question, schedule for a total period not plus 60 months defect liability period less than the stipulated period from the completion certificate. of the completion of the work in question, plus 24 months The EMD of Rs. 10 Crores paid by defect liability period from the the successful bidder at the time of completion certificate. filing of bid through D.D or B.G will be discharged after submission of EMD The EMD of Rs. 30 Crores calculated at 2.5% of bid. paid by the successful bidder at the time of filing of bid through D.D or B.G will be discharged after submission of EMD calculated at 2.5% of bid. 5 Vol-1-NIT- The retention amount from the bills The retention amount from the Clause-31- will be deducted at the rate of 7.5%. bills will be deducted at the Special rate of 7.5%(Seven and half conditions- percent Only) as usual which Sl.No.16. may be released on request of the Agency in multiples of 25/50 Lakhs on production of valid BGs. However, the final retention of 2.5% will be in cash only as per Tender Reforms issued. 6 Vol-1-2. ITB- Bidder/Partners of Joint venture(JV) Bidder/Partners of Joint Clause-1.5 firm have not been blacklisted in any venture(JV) firm have not department in A.P been blacklisted in any department any where previously. 7 Vol-1-2. ITB- That Bidder/ Partners of Joint Venture Deleted Clause-1.5 (JV) firm have not been demoted to lower category in any department in A.P. FOR NOT FILING THE BIDS AFTER BUYING BID SCHEDULES IN A WHOLE YEAR AND THEIR Registration have not been cancelled for a similar default in two consecutive years. 8 Vol-I- 2.ITB- Bidder shall submit only one Bid for the Electro-Mechanical Clause 6.0 work in response to invitation for Manufacturer can be JV bidding. Any bidder who submits or partner in more than one JV. participates in more than one bid will be disqualified and will also cause the disqualification of the consortium/joint venture company in which is a member 9 Vol-I- 2.ITB- Sl No.6- Service Tax at 2.04% on Sl.No.6- Service tax at 4.12 % Clause 18.0- items applicable. on items applicable. Special Note:2 Central Sales tax and Excise Note: 2 The bid offer shall be Attention- duty are placed beyond the scope of exclusive of Excise and Sl.No18.1- this bid and will be reimbursed on the custom duty. They shall be production of evidence of payment. reimbursed on production of evidence by the Agency for having paid such amount to the competent authority. 10 Vol- Information/ Data pertaining to Information/ Data pertaining to Clause20.0(i) Bidders Organization, , Financial Bidders Organization and Part-I: Capability and Technical Capability as Managerial Capability, Eligibility & per statements 1 to 6 ,Vol - I Part-C. Financial Capability and Technical Technical Capabilities as per Stage Format B2, Format-B6 and Format- B8.of Vol I, Part – B- Formats. 11 Volume-1- In respect of cement and steel price In respect of cement and steel Part A- D. adjustment will be made for the price adjustment will be made Cost Control- actual quantity used in the work for for the actual quantity used in Clause.46- increase or decrease of prices by the work for increase or Price more than 5% over current rates ( As decrease of prices by more Adjustment. approved by the Board of Chief than 5% over current rates ( Engineers) of Rs.4300 /- per M.T. As approved by the Board of and Rs. 38,950 /- per M.T. for cement, Chief Engineers) of Rs. and M.S plates respectively. For the 4400 /- per M.T., Rs.41500/- purpose of assessing the increase per MT and Rs.46000/- per and decrease the rates, of cement M.T. for Cement, Steel bars and steel as approved by the Board of (HYSD) and M.S plates Chief Engineers communicated by the respectively. For the Engineer-in-Chief, Irrigation Wing, purpose of assessing the I&CAD Dept., from time to time will be increase and decrease the adopted rates, of cement and steel as approved by the Board of Chief Engineers communicated by the Engineer-in-Chief, Irrigation Wing, I&CAD Dept., from time to time will be adopted 12 Vol-I-D. Cost Control- The above advance shall bear an The above advance shall bear Clause No- interest of 12% per annum. The borrowing rate of Interest as 49.4 interest on the amounts paid as approved by the Government advance is chargeable from the date of A.P from time to time. The the amount is paid. However if interest on the amounts paid completion is delayed by as advance is chargeable circumstances beyond control of the from the date the amount is contractor for which an extension has paid. However if completion is been granted by the Executive delayed by circumstances Engineer / Superintending Engineer beyond control of the the interest charges on such contractor for which an advances shall be waived for the extension has been granted period of extension. by the Executive Engineer / Superintending Engineer the interest charges on such advances shall be waived for the period of extension. 13 Vol-I-Special Superintending Engineer, SRSP- Superintending Engineer, Conditions of FFCCircle-1,Jagtial, Karimnagar Dist. Sripada Yellampally Project Contract- Circle, Mancherial, Adilabad Clause-10.2- Dist. Designs and drawings. 14 Vol-I- From Commercial Operation Date of From Commercial Operation Appendix- the Project, the Contractor shall take Date of the Project, the OM-Terms over the Pump houses and the Contractor shall take over the and Pipeline for operation maintenance for Pump houses and the Pipeline conditions- a period of two years. The Contractor for operation maintenance of Clause-1.0- shall be responsible for the operation civil works for a period of 5 General and maintenance of all components of (Five) years. The Contractor the Project including associated shall be responsible for the hydro-mechanical equipment and civil operation and maintenance of works in accordance with prudent all components of the Project utility practice. including associated hydro- mechanical equipment for a period of 15 (Fifteen) years in accordance with prudent utility practice. To provide all spare parts, To provide all spare parts, 15 Vol-I- tools,equipment,consumables Appendix- tools,equipment,consumables etc. required to operate and maintain the etc. required to operate and OM-Terms maintain the project in and project in accordance with prudent utility practice and keeping in view accordance with prudent utility conditions- practice and keeping in view Clause-2.0- warranty period. warranty period for trouble Scope of free O&M for Fifteen (15) services- Years. Sl.No.10. 16 Vol-I- The Contractor shall obtain and The Contractor shall Appendix- maintain in force throughout during obtain and maintain in OM-Terms Two (2) years of operation and force throughout during and maintenance, Industrial All Risk Five (5) years of Conditions- Insurance for the Project providing full operation and Clause-10- coverage on replacement value basis. maintenance, Industrial All Insurance. Covered peril shall include fire, flood Risk Insurance for the and allied perils. Insurance for Project providing full workers against injury and death as coverage on replacement per Workman Compensation Act shall value basis. Covered peril also be obtained by the Contractor. shall include fire, flood and allied perils. Insurance for workers against injury and death as per Workman Compensation Act shall also be obtained by the Contractor. Upon completion of Two (2) years of Upon completion of Five Kharif O&M period,the acceptance (5) years of Civil works 17 Vol-I- tests shall be carried out before the O&M period,the Appendix- period is taken over by the acceptance tests shall be OM-Terms Employer.These acceptance tests carried out before the and shall be identical to the test after period is taken over by the Conditions- completion conducted under the EPC Employer.These Clause-13- portion of the contract, except that the acceptance tests shall be minimum condition shall be agreed identical to the test after performance value from the EPC test completion conducted reduced by the percentage value of under the EPC portion of contractual acceptance degradation the contract, except that the minimum condition shall be agreed performance value from the EPC test reduced by the percentage value of contractual acceptance degradation The Contractor shall also make The Contractor shall available the proof that maintenance/ also make available the overhaul of equipment was carried out proof that maintenance/ during TWO (2) successful years of overhaul of equipment Kharif years‟ period in accordance was carried out during with the maintenance schedule of the Fifteen (15) successful supplier of the equipment years of O&M period for Electro-Mechanical and Hydro-Mechanical in accordance with the maintenance schedule of the supplier of the equipment Vol-I-Bill of The contractor would be permitted to The contractor would be 18 quatntities- use the excavated useful soils and permitted to use the Preamble- stone for construction purpose. Soils excavated useful soils and Clause.25 used for construction either for stone for construction homogenous section in hearting or in purpose. Soils used for casing zone based on the suitability construction either for will be at free of cost and the cost of homogenous section in stone used for construction purpose hearting or in casing zone will be recovered from the contractor‟s and the stone used for bill. The contractor should quote his construction purpose bid price keeping in view of the above based on the suitability aspects. will be at free of cost. The contractor should quote his bid price keeping in view of the above aspects. However Seigniorage charges etc., will be recovered as usual,as per Cl.104 of Other General Conditions of Vol. I of Bid- document. Volume-1- Part-D-Basic The Objective of this Package work is The Objective of this 19 Project lifting of 136.24 TMC of water from Package work is Drawl of parameters- Ragampet(V) ,near Kakatiya 114.24 TMC of water Clause-1.0- Canal,Choppadandi(M) Karimnagar from Ragampet (v) Objective District to Mothe Vagu Reservoir by near Kakatiya Canal in water conveyor system with all 90 days to drop in associated components Motevagu Reservoir duly linking of existing Flood Flow Canal to feed Mid Manair Reservoir by water conveyor system with all associated components. . . 20 . Volume-1- 1) Lifting of 114.24 Part-D-Basic 1) Lifting of 136.24 TMC TMC of water in 90 Project of water in 90 days in days in Single parameters- Single Stage from Stage from Clause-2.0.1- Ragampet (v) near Ragampet (v) near Main Kakatiya Canal Kakatiya Canal Components. 2) Gravity Lined Canals and 2) Gravity Lined Link Canals to existing Canals and Link FFC including formation of Canals to existing . embankments with FFC including discharge capacity of 500 formation of Cumecs. embankments with 3) Lined Tunnels, Surge discharge capacity of pool, Adits, Rockledge 419.00 Cumecs and Draft tube tunnels 3) Lined Tunnels, for required discharge Surge pool, Adits, and length. Rockledge and Draft tube tunnels for required discharge and 4) CM & CD works for Gravity length. Canals. 4) CM & CD works for Gravity and Lead Channels. .” . . 21 Volume-1- The detailed investigation of Main The detailed investigation Part-E-Project Canal alignment about 12.500 Km of Gravity Canal alignment Profile- (approx.) and lined Tunnels of about about 4.25 Km (approx.) System 9.00 Km (Approx.) to carry capacity of and lined Twin Tunnels of Requirements 500 Cumecs. and H.Ps. are to be got about 5.0 Km (Approx.) to -A. approved by the competent authority. carry capacity of 419 Investigation- Cumecs and H.Ps. are to Sl.No.3 be got approved by the competent authority. 22 Volume-1- The proposed Main Canal is to run The proposed Gravity Part-E-Project about 3.0 Km (approx) length.The Canal is to run about 4.25 Profile- Main canal proposed is lined Canal Km (approx) length. System and runs with FSL cutting as far as Requirements possible. -B. Design- Sl.No.4 The proposed Gravity 23 Excavation of Main Canal of about Volume-1- Canal is to run about 4.25 3.0 Km (approx) as per approved Part-E-Project Km (approx) length. Hydraulic particulars. Profile- Gravity Canals The scope of work for this The scope of work for this bid is for bid is for the reach from 24 Vol.II-Section the reach Kakatiya Canal near Kakatiya Canal near C-01-Clause Ragampet (V) to Mothe Reservoir and Ragampet (V) to Mothe 1.2.2- linking of existing FFC for a length of Reservoir and linking of about 12.50Km (approx). existing FFC by Tunnels and Gravity Canals. Discharge : 419 Cumecs Discharge : 500 Cumecs Lift head ( Static) : Vol.II-Section 109.10m(approx.) in single 25 EM 01-Clause Lift head ( Static) : 30m (approx.) stage. 1.2- Hydraulics & Other data. Capacity and No.of pumps 26 Vol.II-Section The Pump shall be capable of giving shall be selected and EM 01-Clause rated discharge of 500Cumecs at total designed such that the 1.3- Pump- static head of about 30 M(approx) in Pump shall be capable of Motor-Type two stages at different locations . giving rated discharge of and Rating 419 Cumecs at total static Sl.No.ii. head of about 109.10M(approx) in single stage at Kakatiya Canal near Ragampet (V) Deleted. Vol-II-Part-C- The Clause 1.14- Casing and Stay However, Spiral and EM01-Clause- Column. Guide vane system along 27 1.14.. with water depression system arrangements to be made available. A stay ring of fabricated welded carbon plate steel Vol-II-Part-C- shall be provided between A Sta A stay ring of fabricated welded carbon the regulating ring and the 28 EM01-Clause- plate steel shall be provided between draft tube cone. The ring 1.17.. the regulating ring and the draft tube shall be furnace stress cone. The ring shall be furnace relived. A man hole with stress-relieved. It shall be made bolted cover for access spherical over a portion to minimise shall be provided in the clearance to runner blades. . discharge ring. Guide The stainless steel overlay vane apparatus to be shall be made at the portion of the provided with necessary inside surface surrounding the runner. OPU and governing mechanism with A man hole with bolted cover Servomotor, for effective for access shall be provided in the drainage of shaft seal discharge ring. Suitable provision leakages, two nos. A.C. shall be made for gravity drainage of submergible motor sets leakage water at least two opposite along with necessary level stay vanes. Additionally, for effective controllers for auto drainage of shaft seal leakages, two start/stop of pumps shall nos. A.C. submergible motor sets be provided. One set of along with necessary level controllers additional level switches for auto start/stop of pumps shall be shall be provided for high provided. One set of additional level level and very low level switches shall be provided for high alarms in control room. level and very low level alarms in control room. Slip joint/Dismantling joint shall be provided as 29 Vol-II-Part-C- Discharge valve-valve body-Slip required for dismantling of EM01-Clause- joint/Dismantling joint-not furnished. valve without dismantling 1.25. other arrangement. Ultrasonic type 30 Vol-II-Part-C- Pressure transducer type EM01-Clause- 1.32.5 31 Vol-II, Part-C Four Nos. of suitable type pumps Not more than 10 (Ten) Specification each for discharging not less than 125 Nos. of suitable type for Electro- Cumecs of water. pumps each for Mechanical discharging not less than work-Pump, 41.90 Cumecs of water. clause-1.40, Schedule of requirement. Schedule of requirements-Spares for 32 Vol-II/Part-C Spares shall be supplied 5 years-not furnished. /Section for 5 years of trouble free EM01 operations. 33 Vol-II, Part-C Motors should be capable of starting Motors should be EM03 B by adopting suitable soft starters to Capable of starting by limit the starting current to less than adopting Suitable Soft twice the full load current of the motor starters to limit the starting and limiting the voltage dip in the current of the motor and system within the permissible limits limiting the voltage dip in based on the prevailing fault levels of the system within the the power system at the location. permissible limits based on the prevailing fault levels of the power system at the location. Three Sets of starting equipment of suitable capacity capable to start any motor with any set shall be supplied along with necessary valves, compressors and tanks to dewater the runner chamber of the pump during starting shall be provided for smooth start of the pump. Starters shall be of LCI/SFC type. If however the bidder provides other types technically proven and suitable, then it shall be done with the prior approval from the employer and conditions including price etc., prescribed at the time of approval shall prevail. 34 Vol-II, Part-C Protective Relaying Equipment – If Protective Relaying EM03 Numerical type- Redundancy not equipment is of numerical B/Clause4.2(a furnished. type they shall be ) configured with Redundancy. 35 Vol-II, Part-C Where ever “Segregated phase” Isolated phase EM06-Clause 6.1 36 Vol-II, Part-C One set of 220 V DC Batteries of 500 Two (2) sets of 220 V DC EM12-Clause- AH and One set of 24 V DC Batteries Batteries of 500 AH and 12.0 of 500 AH Two(2) set of 24 V DC Batteries of 800 AH 37 Vol-II, Part-C EM15-Clause- One no. 250 KVA D.G.Set Two(2) sets of 500 KVA 15.1 D.G.Set or 315 KVA D.G.Set 38 Vol-II-Part D- 220 KV Double Circuit Transmission Deleted. 220 KVDC Line Transmission Line 39 Vol-II, Part-A; Not furnished Furnished as addendum -I Section C-20, C-21 and Annexures AC 01 to AC 05 40 Vol-I- Mile stone Programme. Now furnished as Annexure-I Addendum-2 Not furnished. 41 Vol-I- Schedule of Payment. Now furnished as Annexure-II Addendum-3 Not furnished. C.Financial 1. The bidder/firm/company/JV on his 1.The Requirement name should have minimum annual bidder/firm/company/JV 42 financial turnover in all civil / on his name should have of Vol.I mechanical /electrical engineering minimum annual financial works executed of value not less turnover in all civil / than the Rs. = (Approx value of work mechanical/electrical in Rupees/No. of years prescribed for engineering works completion), in any one year during executed of value not the last five years. less than the Rs. = 780.13 Crores in any one year during the last five years.. 2. The bidder/firm/company shall 2. The demonstrate that a single entity / bidder/firm/company shall each member of JV or consortium demonstrate that a single has an adequate bank credit plan to entity / each member of meet the aggregate fund requirement JV or consortium has an of the project i.e., not less than Rs.= adequate bank credit (Approx. value of work in rupees x plan to meet the 0.25/No. of years prescribed for aggregate fund completion) in the proforma enclosed requirement of the project to the bid documents. i.e., not less than Rs.= 195.03 Crores in the proforma enclosed to the bid documents. 3.The bidder / firm / company on his 3.The bidder / firm / name should have satisfactorily company on his name completed similar works i.e., work should have satisfactorily of Pumping stations / Hydro power completed similar works stations / pressure mains / power i.e., work of Pumping plant water system of value not less stations / Hydro power than the value equivalent to Rs. = stations / pressure mains Approx value of work in Rupees/No / power plant water of years prescribed for completion) x system of value not less 25%, in the last seven years and than the value equivalent should be running successfully for at to Rs. = 195.03 Crores least two years. in the last seven years and should be running successfully for at least two years. ADDENDUM-1 SECTION - C 20 EXCAVATION OF TUNNEL/ DRAFT TUBE TUNNEL/ INCLINED SHAFTS 20.1 SCOPE OF WORK: i) The specifications described hereunder cover all labour, materials, tools and plants, equipment and machinery related to the work of Excavation of Tunnel, (i.e., under ground excavation) transportation and stock piling of muck, disposal of muck into dumping areas as approved by the Engineer-in-Charge. ii) The Excavation shall be made to the lines and dimensions shown on the drawings approved for construction or other wise agreed with the Engineer-in-Charge iii) This under ground excavation shall be done by smooth blasting methods including loading, conveying and disposal of the excavated rock spoil, preparation and maintenance of haul roads, ventilation, lighting, supporting and safety measures communication systems, dewatering etc., as approved by the Engineer-in-Charge. 20.2 SUBMISSIONS: 20.2.1 Before initiating the tunnel excavations, the Contractor shall prepare drawings and sketches showing the construction system proposed to be utilized as well as a list of equipments and its characteristics, personnel and their qualifications and shall furnish the same to the Engineer-in-Charge for approval. 20.2.2 The Contractor shall submit for the approval of the Engineer-in-Charge, the schedule that he proposes to follow for several excavation fronts, together with a complete description of the sequence of the different rounds, diagrams of distribution and depth of holes and quantities, type and power of explosives that he is going to use, as well as ignition sequence, type and class of detonators, estimated consumption of explosives per Cubic meter of excavation and all other pertinent data that allows the Engineer-in- Charge to be acquainted with the working procedures and the equipment to be used. 20.2.3 Prior to beginning any work of excavation the Contractor shall submit, for approval, a disposal area plan consistent with the drawings. The plan shall show in addition to the proposed location and size of waste piles, the Contractor‟s plan for excavation describing the sequences and manner in which the material will be handled. Approval of the Contractor‟s plan by the Engineer-in-Charge shall not relieve the Contractor from full responsibility for the adequacy of this programme. 20.3 EXCAVATION OF ROCK: 20.3.1 The rock excavation shall be carried out to the sections, lines and grades as indicated in the drawings approved for construction or as directed by the Engineer-in-Charge. Blasting of rock shall be carried out using explosives most suited to the type of rock met with and permitted by the Engineer-in-Charge, so as to avoid undue over break. The rock faces shall be trimmed so that there are no projections beyond the lines marked on the sections. Blasting shall be carried out at fixed times of the day and all necessary safety measures shall be strictly enforced as stipulated in the section 17 of Technical specifications. 20.3.2 All excavations shall be so done that the rock around the periphery of the excavated final sections shall not be shattered, loosened or other wise weakened. Large over breaks shall be avoided by suitable means such as light charges, ream hole or similar measures. The cost of these measures shall be considered as included in the accepted rate of excavations. 20.4 SETTING OUT OF TUNNEL: The tunnel shall be excavated true to line and grades as indicated on the drawings approved for construction. The line shall be set out by the Contractor at his cost and risk, utilizing the permanent bench marks and station points fixed by the Engineer-in-Charge. Such lines will be checked by the Engineer-in-Charge or his Assistants. The Contractor shall provide all the facilities for such check being exercised, but this shall no way absolve him from the responsibility of the accuracy of lines and grade. If the execution has been done to incorrect line or grade, the Contractor shall rectify all such mistakes at his own cost and any unnecessary excavation done shall be filled back by the Contractor in Cement Concrete M20 or as directed by the Engineer-in-Charge. If the Contractor find it necessary either for the purpose of ventilation or to attain the necessary speed of the work, to sink any shafts or drive any additional adits than shown in the approved drawings, he shall not be paid for and the Contractor shall have to plug these back at his own risk and cost with such materials and in a manner as may be directed by the Engineer-in-Charge. Bore holes are to be drilled to ascertain the geology of the rock expected in the excavations and the treatment if any required during execution shall be clearly discussed before approval of the drawing. The Contractor shall excavate sumps in the Tunnel as may be required after approval of the Engineer-in-Charge. In special location and close to profile lines where specifically ordered by the Engineer-in- Charge, the use of explosives shall be discontinued and the rock excavated by line drilling, broaching, barring, chiseling or wedging etc., as may be approved by the Engineer-in- Charge. 20.5 DRILLING: Drilling shall be done by the wet drilling method. 20.6 TRIMMING OF FACES: After blasting, the whole area of excavation shall be carefully examined, and all loose rock, projections etc., removed in such a way that there shall not be any danger of any pieces of rock falling down, subsequently due to any cause what so ever. After the section is excavated it shall be carefully trimmed by using light explosives, if necessary to remove any projection that may be found within the boundaries defined by the minimum excavation lines. 20.7 INTERMEDIATE CONCRETING: When ever the Engineer-in-Charge considers that it is necessary to protect weak rock by placing the concrete lining in part or in full, immediately the Contractor shall carry these works. 20.8 ASSISTANCE FOR VERIFICATION: No distinction shall be made on account of the materials being wet or dry. The quantities of excavation shall be measured as solid excavation in site. The Contractor shall provide suitable rig or any other approved equipment and make all necessary arrangements to the satisfaction of the Engineer-in-Charge for moving the rig along the alignment and grade of the tunnel, shafts etc., to check dimensions of the minimum excavation lines, as and when required by the Engineer-in-Charge. 20.9 SUPPORTS AND GENERAL SAFETY REQUIREMENTS: The Contractor shall take full responsibility for the safety of all underground excavations. He shall also be responsible for the adoption and fulfilling of all necessary measures to protect his workers from slides and cave-ins from the roofs, walls or at the work fronts, fortuitous explosions, intoxications, traffic accidents, electric discharges and all accidents of probable occurrence in the excavation works. The Contractor shall take all precautions necessary for the above safety measures. Lack of compliance with any safety measures or requisites indicated herein shall be sufficient cause for the Engineer- in-Charge to suspend the work until the causes that lead to the suspension are remedied. The Contractor shall have no right to claim extension or compensation for this reason. Dust resulting from drilling shall be avoided by using water and using forced ventilation. At any sections of the tunnels where the rock met with its unstable, shall be permanently supported in an intermittent or continuous way by means of steel supports with permanent or temporary laggings placed as required by local conditions, with the prior approval of Engineer-in-Charge. In areas where supporting by means of shotcreting using Dramix Steel fibers and rock bolts is required, the same shall be provided as expeditiously as possible and as directed by the Engineer-in-Charge. As soon as the Contractor meet with such situations, he shall report to the Engineer-in-Charge and obtain his orders. 20.10 EQUIPMENT: Electrical, pneumatic or diesel equipment can be utilized for the different operations involved in the excavation of tunnels. Gasoline-powered equipment shall not be permitted in tunnels or underground works. In case the diesel equipment is used, the Contractor shall provide the necessary facilities to remove all obnoxious gases, resulting from the operation of the equipment. The equipment shall have inbuilt scrubber to keep down emission of obnoxious fumes to the minimum. If the diesel gas removal system is not adequate, the Engineer-in-Charge may order the suspension of all operations till the necessary measures to correct the defects of ventilation system are taken. No claim in this regard shall be allowed. 20.11 LIGHTING: 20.11.1 For each tunnel, shaft etc., the Contractor shall provide a lighting system which shall be maintained in operation during the execution of the respective work. Besides the general lighting system, he shall provide special lighting for the excavation front, where any work is being executed or where it is necessary to inspect a part of the work. This lighting system shall be integrated by flood lights or any other type approved by the Engineer-in-Charge. Energised wires or lamps, bulbs shall not be permitted in the immediate vicinity of the work front at the time of charging and blasting. Lighting of flame shall not be permitted in any section of the work unless the Engineer-in-Charge authorizes it for specific working conditions. All the roadways/tunnels through which persons pass should be kept effectively white washed within 100m from their farthest face. Particular care should be taken to places including junctions siding, bye-pass, engine room place containing motor/ or other apparatus, first aid station etc., 20.11.2 All power and lighting wires shall be installed and maintained in optimal conditions of insulation and safety confirming to the Indian Electricity Rules 1956 of Government of India. Power and lighting wires shall be installed on one side of the tunnels, shafts and caverns and the detonator wires shall be installed on the opposite sides and at sufficient distance from telephone or wires of communication system. 20.11.3 All electrical cables, wires shall be firmly fixed on excavated walls, by means of insulators of adequate design and capacity and their installation shall be made in such a way that wires do not get damaged during excavation works. The Contractor shall provide sufficient lighting to ensure the following, in all places where work is in progress: 1. Safe working conditions are provided for the Contractor‟s personnel, other Contractor‟s employees, personnel of the Engineer-in-Charge, occasional visitors etc 2. The work can be constructed in complete compliance with the Contract. 3. A complete inspection of all works in progress can be made by the Engineer-in-Charge. 20.11.4 Unless otherwise directed by the Engineer-in-Charge the minimum service illuminance on ground or working surface to be provided for the various operations or work areas shall be as tabulated below: Operation or Area Illuminance Minimum measured value lux Access and haul roads where cross traffic or other hazardous 10 conditions exist Bridges 10 Concrete placing 50 Underground works (Working faces) 50 Junction 15 Operator‟s cabin of machines 30 Maintenance shops and auxiliary buildings 200 20.11.5 The Contractor shall supply a suitable instrument to the Engineer-in-Charge for measuring the intensity of illumination. The instrument shall comply with BS:667 20.11.6 Illumination for areas or operations not listed in the above table shall conform to the requirements of the lighting guide, building and civil engineering sites (illuminating Engineering Society, London) 20.11.7 All mobile equipment or plant used during night operations or in underground shall be equipped with sufficient lights and reflectors to ensure safe working conditions. 20.11.8 Not less than 14 days before the start of tunneling or night operations, the Contractor shall submit his proposals for lighting in the tunnels, shafts and caverns and in the areas in which he proposes to work at night to the Engineer-in-Charge. The Contractor shall modify the proposals if required by the Engineer-in-Charge and shall not begin operations at night or in underground as the case may be, until the proposals for lighting (in an amended form if required) have been approved. Approval of the Contractor‟s proposals for lighting shall not relieve the Contractor of any of his liabilities or obligations under the Contract. 20.12 VENTILATION: 20.12.1 The Contractor shall furnish and install in each one of the underground work fronts and in each tunnel, a ventilation system which will be maintained in operation during the time in which work is being executed. The ventilation equipment and ducts shall be of good quality so that a continuous service is guaranteed, have an adequate capacity and be firmly fixed and sufficiently strong to withstand the work pressures. The tail end of the ventilation duct shall be taken to a place as close to the work as allowed by the blastings. Thereafter arrangement for supplying fresh air at the face for effective an quick clearance of blasting fumes, gases etc., a flexible extension pipe shall be used. The Contractor shall submit for the approval of the Engineer-in-Charge, all ventilation drawings and general layout indicating the number of fans and their capacity before initiating any underground work. The Contractor shall not work without this approval which however does not relieve him from his obligation to provide sufficient fresh air for underground work. If during the execution of the work, it is found, in the opinion of the Engineer-in- Charge, that the capacity of the ventilation system is inadequate for the good health of the workers and for removing the gases as prescribed below, the Engineer-in-Charge may order the Contractor to install additional fans and take all necessary measures to obtain the desired results. Adequate arrangement should be made to circulate as much quantity of air upto the site of blasting as to ensure after every round of blast dilution of co and oxides 50 PPM and 5 PPM respectively within a period of 5 minutes. It should be ensured that at every place where persons are required to work or pass, the air does not contain less than 19.5% oxygen or more than 0.5% of carbon dioxide or any obnoxious gas present in quantity likely to affect the health of any person. The Contractor shall have no right to any compensation or to term extensions for this reason. 20.12.2 The carbon monoxide (CO) content and the percentage of the oxygen in the air shall be measured and checked regularly after half an hour of each blasting and once between the two consecutive blastings. If the CO content in the air exceeds 50 PPM or the percentage of the oxygen in the air is less than 19.5% at any place, the reduced rate shall be given for the item of excavation as under: 20.12.3 If CO content is between 50 to 60 PPM the excavation rate shall be reduced by 10% and if oxygen content is between 19.5 to 19%, the excavation rate shall also be reduced by 10%. The work shall be stopped after the CO content exceeds 60 PPM and the percentage of oxygen reduced below 19%. In case of persistent failure to adhere to the standards and requirements laid down above, the Engineer-in-Charge will be free to take either of the following two actions at his own option: (1) install and operate at the cost and risk of the Contractor, such supplementary ventilation facilities as he may deem necessary, or (2) terminate the Contract after giving the due notice. 20.12.4 The ventilation provided for each work front shall furnish sufficient fresh air for all the personnel in the underground in order to avoid a concentration of contaminants 3 dangerous for the health and lives of the workers and supervisors. At least 5 m /min/bhp of air should be circulated in the roadways where the diesel equipment is in use. In 2 normal approaches/ drainages of approximately 10m cross section, which are 50m or 3 more in length a suitable auxiliary fan should be provided to ensure atleast 150 m /min 3 ventilation air currents within 4.5m of the faces in normal conditions and 284 m /min at the time of blasting and the time following the blasting. The minimum amount of fresh air 3 3 shall be 4.25m per minute per person. In addition 5 m of air per minute shall be applied per brake horse power of diesel equipment. In addition to the above limit the ventilation systems shall have a minimum capacity which allows the withdrawal of all gases and dust resulting from a blast within a period of time not more than 15 minutes, so that after this time has elapsed, all operations can be resumed. No person shall be allowed to re- enter the place where blasting has been carried out unless a period of at least 15 minutes has elapsed from the time of blasting. 20.12.5 Ventilation and exhaust system for the excavation of caverns, tunnels and shafts shall be of sufficient capacity to maintain an adequate supply of uncontaminated pure air at all points. The design of ventilation system shall take into account, factors such as length of heading, size of tunnel/shaft/caverns, amount of explosives used, frequency of blasting, temperature and humidity and safe limits of endurance for human being to toxic gases. o The wet bulb temperature in any working place should not exceed 33.5 C and where the o wet bulb temperature exceeds 30.5 C arrangement shall have to be made to ventilate the same with a current of air moving at a speed of not less than 1m/sec. All the ventilating and lighting arrangements specified in this section shall be considered as part of the items of underground excavation by tunneling and no extra payment for this shall be made. 20.13 NOISE CONTROL: 20.13.1 Noise is considered to be impulse when the variations in level involve maximum at intervals greater than one second; when personnel are subjected to sound levels exceeding the limits specified in this section, feasible engineering or administrative controls shall be utilised. If such controls fail to reduce sound levels within the specified limit, personal protective equipment shall be provided and used to reduce sound levels to the specified limit. The following standard shall have to be maintained for works for 8 hours duration work. 1. A work limit value of 85 Db (A) continuous may be set as the level below which very little risk to an unprotected ear, of hearing impairment exists for an eight hour exposure. 2. The danger limit value shall be 90 Db (A) above which the danger of hearing impairment and deafness may result from an unprotected ear. 3. A worker should not be allowed to enter without appropriate ear protection, an area in which the noise levels is 115 Db (A) or more. 4. Personal protective equipment shall be worn, if there are single isolated outbursts of noise which can go above 130 Db (A) „Impulse‟ of 120 Db (A) „Fast‟. 5. No worker shall be allowed to enter an area where the noise level exceeds 140 Db (A) 20.13.2 In all cases where the sound levels exceed specified limits, a continuing, effective hearing conservation programmes shall be administered. Sound pressure level measurements shall be made by qualified personnel using calibrated instruments. Noise hazardous area (greater than 85 Db(A) continuous or 130 Db(A) impulse or 120 Db (A) „Fast‟) will be marked with caution signs indicating both the pressure of hazardous noise levels and the need for hearing protection. 20.14 DUST CONTROL: The average concentration of respirable dust in the work front during each shift, to which 3 each worker is exposed at any working point or place, shall not exceed 3 mg/m . This limit value will be applicable when the respirable dust contains 5% or less of free silica in air borne dust. Where dust contains more than 5% quartz or free silica the limiting value shall be determined by the following formula 5 3 Percentage of respirable quartz or free silica mg/m 1. All respirable dust concentrations shall be measured by the NCB/MRE Dust sampler type 113 A of UK or its approved equivalent. 2. The minimum frequency for determination of the respirable dust concentrations shall be once a month at different working points. 3. Dust control measures should be adopted if the concentration exceeds the limit below five micron size. The dust control measures are several including thorough wetting of the surfaces at locations which produce dust for example the areas to be blasted, loading and unloading places, crushing or dressing of stones etc. Another effective dust control measure is the provision of suitable dust respirator where the permissible limits are exceeded. 4. From the drilling and blasting point of view the dust control measures include: a) Wet drilling b) Before any shots are fired, the roof/back hanging wall, footwall and sides in the vicinity shall where practicable and unless naturally wet throughout, be thoroughly wetted with water. c) As far as practicable, the times for shot firing shall be so chosen that a minimum number of persons are exposed to dust. d) After shots have been fired (i) airborne dust in the place shall be actively removed by a current of air and (ii) after the place has been examined and declared safe, the face, walls and sides and all loose rock within a radius of 4.5m of the site of blasting shall be thoroughly wetted with water e) Dust suckers may be used in dust laden atmosphere 20.15 COMMUNICATION FACILITIES: The Contractor shall install and maintain proper communication facilities in good working order at all times during the whole period of the work concerned at or near the working face of the tunnel, shaft and caverns etc, as well as other points so as to afford prompt communication over telephone, with some responsible employees of the Contractor outside the tunnel, shaft and caverns, etc. The Contractor shall also install, maintain and operate such other communication and signal facilities as may be necessary for the safe and efficient execution of the work. All such facilities shall be subject to the approval of the Engineer-in-Charge. Employer shall have free use of such communication and signal facilities. 20.16 TUNNEL EXCAVATION THROUGH ROCK NOT REQUIRING ANY STEEL SUPPORTS: Rock bolts with shotcreting are proposed to be provided as support wherever necessary as per approved drawings. The excavation and support installation operation shall be made in a coordinated way to avoid the creation of unbalance forces on the tunnel sections. 20.17 SMOOTH BLASTING: 20.17.1 Smooth blasting technique shall only be adopted for tunneling and shall be in accordance with the following. The smooth blasting will require closely spaced contour holes, carefully, aligned and lightly loaded to obtain satisfactory smooth blasting results. A well excavated surface should show on the rock face the traces of at least 75% of the drill hole traces distributed uniformly in the peripheral Rock surfaces exposed by each round, after scaling down of all loose and shattered rock liable to fall before or during rock reinforcement installations. In this method, closely spaced holes are drilled along the final perimeter of the excavation and are blasted in a single round along with the production holes using suitable delay detonators in between. Alternatively, a bark of about0.8M to 1.0M may be left along the periphery of the caverns, tunnels etc., in the previous blast and this bark would then be blasted after drilling closely spaced holes along the perimeter in the next round of the blast along with its production holes. The method which will give the best results would be adopted. 20.17.2 Before starting the excavation, the Contractor shall make, a series of test blasts in areas different than the final excavation surfaces of the tunnel, cavern etc, to demonstrate that the drilling patterns, spacing of the contour holes, blasting delays, loading etc, are satisfactory to obtain the required results. If the Engineer-in-Charge is not satisfied with the drilling and blasting pattern proposed by the Contractor, the Contractor should arrange to get the blasting design from a reputed organization/laboratory and should adopt such blasting design with the approval of the Engineer-in-Charge. 20.17.3 Based on the tests, the details of the method of smooth blasting shall be finalized and got approved by the Engineer-in-Charge. The approval of the proposed method or methods for excavation, support of installation, transportation and co-ordination of operations, shall be made based on the efficiency of the proposed plan, but the approval shall not absolve the Contractor from the responsibilities during the execution of the work as required by these specifications and the details shown on the approved drawings. 20.17.4 The length and number of holes, the charge of gelatin per hole and the sequence of detonation shall be determined with the purpose of reducing the over excavation to the very minimum and maintaining the periphery as close as possible to that shown on the approved drawings. Necessary precautions in determining the above should be taken to minimize over excavation. If the systems adopted by the Contractor cause over breakage out side the allowable limits, by Engineer-in-Charge may ordered the change of system as deemed necessary and the Contractor shall not claim any compensation extra over the quoted price. 20.18 CAVE-INS IN TUNNELS The Contractor shall, at all times, take all the measures deemed necessary or ordered by the Engineer-in-Charge to avoid Cave-ins in Tunnels. In case a Cave-in occurs or the signs indicating the possibility of its occurrence are observed, the Contractor shall take all necessary measures to avoid its further spread and prevent accidents and shall notify immediately the Engineer-in-Charge. In such cases, the Contractor shall take all measures ordered by the Engineer-in-Charge. The Contractor shall carryout all works required to control the cave-ins including those ordered by the Engineer-in-Charge. The removal of caved-in materials, the necessary repairs and the accidents that may occur shall also be the Contractor‟s responsibility. The Contractor shall have no right to request for extension of time for the completion of the works, if the delay is due to the fault of the Contractor. 20.19 EXCAVATION OF TUNNELS THROUGH ROCK REQUIRING PERMANENT STEEL SUPPORTS: The Contractor may be required to excavate some sections of the tunnels through weak or weathered rock by means of acceptable methods which allow a permanent control of the front and avoid cave-ins and slides. He may also use the excavation and transportation equipment that best suits the working conditions with the approval of the Engineer-in-Charge. The excavation shall b coordinated with the installation of laggings with structural steel supports and with the back filling operation behind supports to provide an immediate permanent support for all the material surrounding the tunnel. Where such zones of rock are found the excavation shall be started using manual methods or pneumatic tools in order not to disturb the neighboring materials. In case, it is impossible to execute the excavation using these methods and it becomes necessary to resort to explosives, blasting shall be made in a controlled manner. However, only smooth blasting method shall be used everywhere, as per the pattern approved by the Engineer-in-Charge. When supports and laggings are placed, they shall be tightly packed at their contacts with the roof and walls in such a way as to give positive support to rock and prevent its sagging and thus to obtain a safe protection. 20.20 TEMPORARY SUPPORTS: With adoption of smooth blasting, immediate shotcreting with dramix steel fiber and provision of permanent supports where required and within specified period after blasting, it is felt that there will be no situation where temporary supports will be required. However, these shall be erected by the Contractor when so directed by the Engineer-in- Charge. Consequences if any for his failure to do so in proper time shall be the sole responsibility. The methods, the extent of supporting, sizes and spacing of supports etc, shall be as approved by the Engineer-in-Charge. This shall also include temporary supports or propping that may be needed before fixing supporting bolts. The stipulations given for permanent supports shall apply in this case of temporary supports also. The supports shall be of steel or timber and they shall be removed before placing the concrete lining. The members of the supporting frame work proposed to be left should not reduce the minimum thickness of concrete lining as shown in the typical supported sections on the drawings. All the material from the temporary supports removed shall be the property of the Contractor. 20.21 EXCAVATION AT TUNNEL JUNCTION AND CORNERS: Special care and precautions shall be taken to carry out excavation at tunnel junctions to avoid over breaks. Spacing of the contour holes in the drilling pattern should be reduced and the blasting charge adjusted in the shell or bark blasted last in the zone adjacent to the final excavation lines to give the desired results. 20.22 SEALING AND TRIMMING OF ROCK: After the face is blasted, gases removed and the face ventilated all loose or loosened rock from the top and sides shall be removed as quickly as practicable by approved methods to avoid danger to workmen and equipment later. If any loose or loosened rock is noticed anywhere in the excavation it shall be removed expeditiously. As the work advances, trimming of rock surfaces remaining within the minimum excavation line shall be undertaken simultaneously. In no case shall trimming be postponed and left to be tackled last. 20.23 TREATMENT OF FAULTS AND MINOR CRACKS IN TUNNELS: During the excavation of the tunnels some cracks, shearing zones and/or faults, may be found which do not require support as determined by the Engineer-in-Charge. The treatment of these zones is indicated below. The Contractor shall remove all the material filling the crack or fault down to a depth as directed depending on the width of the crack. Its surface shall be cleaned with water and air jets. If some types of lining is planned for this section of the tunnel, the same shall be provided as directed by the Engineer-in-Charge. Rock bolts will be required to be provided as determined by the Engineer-in-Charge, if that section is to remain unlined. Besides fixing of rock bolts shortcrete reinforced with welded Steel Fiber shall be used to fill and cover the crack according to dimensions and details ad directed. 20.24 EXCAVATION OF AUXILIARY TUNNELS: In order to complete the construction of the underground work in the prescribed time it may be necessary to drive Auxiliary tunnels not included in the scheme of works put to tender. The Contractor shall propose the location of such tunnels so that the stability or operation of any present or future work is not disturbed. The Engineer-in-Charge will study the proposal and may approve or reject it. The approval of the Engineer-in-Charge does not in any way absolve the Contractor from his responsibility for damages and inconveniences that may arise from the excavation or the present of such tunnels. The Construction of Auxiliary tunnels shall meet the requirements stipulated for tunnels. 20.25 EXCAVATION OF ADIT AND TUNNELS: Besides other provisions, it is necessary to take the following into account for the excavation of the Adits and Tunnels. The Contractor shall select the most proper excavation method, either with excavation in full section or in heading and benching etc. The Contractor shall clearly indicate in his proposals with sufficient details of the method that he intends to use such as full face or heading and benching. This information shall also include proposed drilling and blasting patterns and equipments to be used for each Adit and Tunnel. 20.26 EXCAVATION LINES IN CASE OF ENLARGEMENT AND OVER BREAKINGS DUE TO NATURAL CAUSES: Any enlargements considered necessary by the Contractor for the convenience of his work may be done by him with the prior approval of the Engineer-in-Charge. This shall be back filled with concrete of a class similar to the lining at his cost. 20.27 SUPPORTING SYSTEMS FOR TUNNEL: In portions of the sections of work, it may become necessary to support rock by permanent structural steel supports and excavation may have to be increased to accommodate the supports. The proposals and the drawings for placing supporting system with permanent structural steel shall be got approved by the Engineer-in-Charge before taking up it. All type of supporting systems, their components, methods and procedures of furnishing, installation and manufacture shall confirm to Indian standard specifications and its subsequent revision and other publications listed below unless other wise specified. IS:226-1975 Structural Steel (Standard Quality) IS:800-1982 Code of practice for use of structural steel in general building construction IS:8266-1976 Expansion shell type roof bolts IS:1786-1979 Structural Steel (Standard Quality) IS:1363-1967 Black hexagon bolts, nuts and lock nuts and black hexagon screw IS:1368-1967 Dimension of ends of bolts and screw IS:2108-1962 Black hearth malleable iron castings IS:1030-1974 Carbon steel casting for general engineering purpose IS:269-1971 Ordinary and low heat Portland cement IS:1343-1980 Code of practice for pre-stress concrete IS:6003-1970 Specification for intended wire for pre-stress concrete IS:6066-1971 Recommendation for pressure grouting of rock foundations in river valley Projects IS:1521-1960 Method of tensile testing of steel wire Wherever necessary, placement of steel supports or installation of rock bolts shall be done as soon as possible after excavating of each face is finished and in such a way that the natural cohesion of the rock is optimally used. Erection of supports shall be done in such a way as to keep grades and alignments of tunnels in accordance with the approved drawings. All ribs shall have a steel base plate which will be set on steel channels, concrete blocks using also steel wedges in order to avoid sinking of the supports. 20.28 DEWATERING: Dewatering shall be carried out as necessary during the whole contract period. The whole system shall be so designed as to cater for discharges due to seepage and leakages that may find way into any of the work area. The design capacities and general arrangements of all installations shall be got approved by the Engineer-in-Charge. The Contractor shall provide required gutters, adequate drainage systems, sumps and install and operate necessary pumping equipments. The Contractor shall take abundant care to safe guard pumps and all other accessories for dewatering and no compensation what so ever shall be paid for any claim likely to occur in such a case. If any damage to his own work is caused due to failure of dewatering arrangements, the Contractor shall have to set right such damages with his own cost. If such failures cause damages to works of other agencies/department it shall be set right with his own expense. In case the Contractor, for any reasons, suspends his dewatering operations for any period but the dewatering considered essential by the Engineer-in-Charge, the Engineer- in-Charge shall have the liberty to take over this operation of dewatering and recovering the amount spent on this by the Engineer- in- charge. SECTION - C 21 DELIVERY MAINS 21.1 Scope of Work The specification described herein under cover all labour, materials, plant, equipment and service related to the handling, fabrication, transportation, erection, painting, testing and commissioning for steel liners and its accessories from high tensile steel plates, concreting around steel liners in the tunnel pack grouting, consolidation grouting, concreting for Rockers Pedestals & Anchor block including manufacture, transport and supply of expansion joints to be carried out by the Contractor under this contract. The Contractor has to set up his own site workshop for cutting, bending and shop welding of the plates. All the machinery, tools and plant including plate bending machine required for successful completion of the work envisaged in the contract are to be procured by the Contractor at his cost. 21.2 Submissions: Atleast thirty days before starting the execution, the contractor shall submit the following item as under to the Engineer-in-Charge. a) The standards of steel plates proposed to be utilized to be specified. b) Fabrication drawings of all the straight shells c) Development drawings for bends, reducer cones and bulkheads and their fabrication drawings. d) Drawings of manhole arrangement and drawings for piezometer connections grout holes etc., e) Drawings for Expansion joints f) Steel liner assembly drawing indicating the shell numbers position of manholes grout holes, stiffener rings, back up plates and other important features and clearly identifying the shop welds and field welds. g) Drawings showing edge preparation details (weld groove design) and any other relevant details for the various types of joints involved. h) Statement showing weights of the fabricated components intended to be billed duly supported by the computations. i) Drawings indicating identification markings intended to be made for radiographic inspection of welds. j) Drawings showing the details of embedments or rail track and other arrangement intended for handling and track and other arrangement intended for handling and erection. k) Any other drawings or calculations that may be required for the execution of the work l) The Contractor shall certify that drawings furnished by him, have been checked before submission and he shall be responsible for the correct fitting of the parts. The Contractor shall submit the drawings exhibiting plate cutting schedules clearly identifying as to how the Contractor intends to utilize each of the steel plates and get them approved by the Engineer-in-Charge before starting of fabrication work. 21.3 Materials 21.3.1 The steel plates shall be in confirmation to the relevant IS Standards. Before bringing the steel plates to the site, the Contractor shall furnish the quantity check certificate issued by the manufactures (SA12/TISCO) to the Engineer-in-Charge 21.3.2 The materials used in the fabrication and erection of the steel liner shall comply with the specifications as laid down in section-6 of this Document. Where materials are not specifically covered by detailed material specifications, the Contractor shall furnish the best available commercial grades of materials or articles to the satisfaction of the Engineer-in-Charge. 21.4 At least 30 days in advance of the transportation of steel plates and steel liner assemblies to the site of erection, the Contractor shall supply, the following details to the Engineer-in-Charge for approval. a) Method/Procedures for handling and transportation of various assemblies, specials and equipment to be used. b) Arrangement/procedure for handling/erection of steel liner assemblies and specials etc., into the tunnel along with details of equipment to be deployed, procedure for alignment and welding in field. c) Detailed procedure for sand blasting and applying necessary primer etc., in shop and coats of paint to be applied in shop/field along with necessary tests therefore. d) The Contractor shall submit along with each consignment of assemblies, accessories of steel liner, the parts catalogue in English language especially prepared to cover all the work/items of equipment furnished under these specifications which may be painting and repair. All name plates, instruction plates, warning signs and any marking whatever on the equipment and its parts and accessories shall be in English language. 21.5 Atleast 30 days prior to commencing radiographic examination, the contractor shall submit details for all radiographic equipment, process and procedures for the approval of the Engineer-in-Charge. The type and make of the radiographic films intended to be used shall be got approved from the Engineer-in-Charge The Engineer-in-Charge reserves the right to call for any additional information deemed necessary to be included in the submitted documents. 21.6 STANDARDS The designs, fabrication, installation, painting and testing of steel liner shells, shall conform to the following Indian standards or where not covered by these standards to the equivalent international standards. a) Steel plates and other material Sl. Material Standards No. 1 Steel plates for steel liners 14mm to 25mm I.S. 2002 Grade.III thickness 2 M.S.Bolts, studs, nuts and washers IS:1364 Grade S-Semi Precision or equivalent 3 Stainless steel for piezometer plugs BS:970-EN-56-A or IS:570 (Schedule V) or equivalent 4 Gaskets or jointing materials BS:1737 or relevant IS specifications 5 Welding electrodes IS:814 6 Paints - Zinc Rich primer AWWA specification of equivalent IS specifications 7 -Cold applied coal tar epoxy paint AWWA Specification or equivalent IS Specifications b) Welding IS:2825 -1969 Code for uniformed pressure vessels ASME Boiler and pressure vessel code of American Society of Mechanical Engineers c) Painting AWWA-C-203-78 Coal tar protective coating and lining for steel water pipe Lines standard of American water works Association d) Inspection IS:2825-1969 As in (b) above And ASME code e) Testing AWWA-C-203-78 As in (C) above SNT-TC-IA Recommended practice for nondestructive testing personnel qualification and certification of the American society In case of the conflict between the above standards and these specifications given herein these specifications shall take precedence. 21.7 FABRICATION 21.7.1 The concentration of the welded joints shall be such that no two main seams come together under an acute angle or cross each other. Where it is not possible to comply with this requirement, the intersection of these welds shall be radiographed, 100mm each side of such intersection. The longitudinal joints shall be staggered, at least by five times the thickness of the thicker plate. Longitudinal seams of steel liner sections shall not intercept the openings provided for manholes and piezometer connections etc. The designs, size and location of these openings shall be selected as required in IS-2825 1969. Manholes shall be provided with suitable handles, flanges and covers, properly machined and shall be complete with bolts, nuts, washers, gaskets etc., 21.7.2 CUTTING OF PLATES AND PREPARATION OF EDGES No cutting of plates shall be started without getting relevant drawings showing cutting schedules approved from the Engineer-in-Charge. Where plates to be welded need cutting to size and shape or squaring in shop following broad guidelines shall be adopted. Cutting can be done by machine or flame cutting. Where the plate thickness does not exceed 25mm, cold shearing may be allowed by Engineer-in-Charge provided that the sheared edge is cut back by machining or chipping for a distance of one quarter of the plate thickness but in no case less than 3mm. Plate edges shall be made in conformity with the specification drawings to suit „V‟ or „U‟ welds as applicable to various thickness for all longitudinal and circumferential welds in shop and field welds for ferrules to be erected over ground. Edge preparation for all circumferential joints in field for the steel liners to be erected in the shaft tunnels shall be to suit single „U‟ or „V‟ joint with backing strip. While making of plates shall be as per approved fabrication drawings, Standard/accepted procedure for marking, edge of steel plates confirming to the above specifications can be prepared by planning, flame burning, chipping, grinding or are gouging. 21.7.3 EDGE PREPARATION: Edge preparation of steel confirming to the above shall preferably be done by planning. In the event of flame cutting followed by chipping and necessary grinding, oxy-acetylene torches may be employed such that basic properties of steel are not affected. In the gas cut edge preparation, 2mm to 4mm of metal shall be removed from gas cut surface by machining or grinding as approved by the Engineer-in-Charge 21.7.4 BENDING OF PLATES: Plates for shell section shall be formed to required shape by cold bending process only such that it does not impair the quality of steel. All plates shall be initially pinch type cold formed/bent on plate bending machine which shall ensure a circular shell from the calculated circumferential length of shell of the required internal nominal diameter. Curvature of bent shells shall be checked with the help of necessary templates. Correction of curvature neither by blows nor by not forming shall be permitted. 21.7.5 PLATES OF UNEQUAL THICKNESS: Where two plates at a welded joints differ in thickness, the thicker plate shall be trimmed to a smooth taper as per IS:2825. 21.7.6 STIFFENER RINGS THRUST COLLARS AND BACKING BARS a) Stiffener Rings and thrust collars i) Stiffener rings and thrust collars wherever required shall be fabricated from minimum number of circumferential sections but welded together and properly fitted and welded to the pipes/ferrules such that the planes of rings shall be normal to the axis of pipes ferrules. ii) The butt welds in a stiffener ring shall be positioned as to have proper staggering with reference to main longitudinal butt welds in the pipe shells. iii) The holes/openings shall be drilled in the stiffener rings as per drawings to permit flow or concrete and the same shall have smooth finish. 21.7.7 BACKING BARS: The Contractor shall use M.S. Flat 75X10mm for field circumferential joints in the tunnel shafts. The method of attachment of backing bar to the pipe shells shall be as indicated in the drawing. The Contractor shall carryout all necessary cutting, machining, welding etc, for preparing and attaching the backing bars. 21.7.8 MANHOLES, NOZZLES ETC. All manholes, nozzles, flanges and other accessories (including covers/O-rings, bolts, nuts, washers, plugs etc) as may be required, shall be installed on the steel liner sections as per the requirement as directed by the Engineer-in-Charge. 21.7.9 BENDS AND REDUCERS Bends shall be made of short segments of pipe with mitered ends and shown on the drawings. Segments of each bend shall be made with equal deflection angles, except for the end ones. The deflection of end segments shall be half the deflection of the central segments. Such segments shall be formed from cut plates, with necessary marking. For change in diameter of steel liner, reducer or expansion pipe shall be provided. The Contractor shall furnish his proposal for preparing testing and transporting and erection of bends and reducer cones clearly indicating extent of work intended to be done at the site workshop as well as during erection. The bends shall be so fabricated as to have a staggering of about 30 to 60 degrees between the longitudinal welds in the consecutive bend courses when installed depending upon the length of plates supplied. 21.7.10 BULK HEADS: Conical type bulk heads if required are to be fabricated and erected by the Contractor. The bulk heads shall be fabricated as per the design and drawings approved by the Engineer-in-Charge to meet the requirement. 21.7.11 ALIGNMENT AND TOLERANCES: Alignment for longitudinal and circumferential joints in shop and circumferential joints in field for shells made from steel conforming to IS 2002-1992 grade.III can be permitted with only minimum number of fit up dogs/cleats which shall be properly welded and neatly removed after alignment to ensure no injury to the parent plates. Before any welding is commenced, it shall be ensured that the chamfered edges are in alignment and that the displacement of the joints is less than: e/50 + 1 + e/2 mm for longitudinal joint and e/50 + 2 e/2 + p/2 mm for circumferential joint here e and p are the difference between the actual thickness if the edges involved and tolerance on the circumference respectively. Other tolerances shall be as specified below or as provided in other acceptable international standards: (a) The variation from theoretical shape of straight piece of a shell shall be less than (+2r/1000) + 2(22) (ef-et) +4) in mm where r=Radius of the shell in mm ef=Effective thickness of steel liner plates in mm et= Theoretical thickness of steel liner plates in mm The external circumference of the completed pipe shells shall not depart from the calculated circumference based on the nominal outside diameter by more than 0.25 percent. (b) Individual Cylindrical shells shall be reasonably square and straight. The straightness of the generating lines of a shell shall be less than 2L/1000 in mm, where L=Length of a shell in mm. (c) The irregularities in profile of a shell (checked by 20 gauge) shall not exceed 3 mm plus 5 percent of the minimum plate thickness. The maximum value may be increased by 25 percent if the length of the irregularity does not exceed one quarter of the length of the shell with a maximum of 1000 mm. (d) The difference between the maximum and the minimum diameters at any cross section of a shell welded longitudinally shall not exceed 0.50 percent of the nominal internal diameter (with a maximum of (D+1250)/200 in mm). 21.7.12 a) Weld preparations whose cross/sectional dimensions vary from those shown on the approved workshop drawings by more than the following tolerances, shall be corrected prior to welding. i) Root opening of joints + 1.5mm ii) Groove angle + or - 5 degrees. iii) Size and location of root face + or - 1.5 mm iv) Radius of „J‟ / „U‟ grooves + 2mm b) The maximum offset (or other defect in alignment) between abutting external surfaces at any position along a butt joint shall not exceed 2 mm for both the longitudinal joints as well as circumferential joints. c) The following limit shall apply to the fit-up of joints to be fillet welded and to the fit-up of stiffener rings (as well as anti-percolation rings) to pipe shells Gap at Joint 2mm maximum This provision is subject to condition that effective throat thickness of the weld shall be not less than that specified in the approved drawings. 21.8 GROUTING AND DRAINAGE HOLES: Holes for grouting in locations as directed by the Engineer-in-Charge or as shown in the drawings shall be required to be made in the steel liner. Necessary plug for grouting holes shall also be fabricated and supplied by the Contractor and same shall be fitted in position and steel welded after needful operations on site are completed. The grout holes shall be sealed by plug after grouting is completed. 21.9 EXPANSION JOINTS: Double sleeve expansion joints as per drawing should be fabricated and erected at site. The chemical composition and mechanical proportion of steel plates used in expansion joints to confirm those of steel plates used in delivery lines. The rate shall include, manufacture, testing and erection at site of work. 21.10 WELDING 21.10.1 Surfaces to be welded shall be clear and free from scale, rust, paint and other matter. All welding will be performed by the electric arc method, using a process that will exclude the atmosphere from the metal and where practicable automatic welding equipment shall be used. All welding shall be done in accordance with the requirements of fabrication and inspection of the ASME code or relevant IS codes for welding of liners and steel pipes. All welding electrodes required for the fabrication/installation of the water conductor steel pipeline shall be furnished by the Contractor. Where weld is deposited in successive layers, such layer shall be cleared of the slag and other deposits before the next layer is applied. Tack weld should be chipped out before final welds are made. On interior surfaces the reinforcement layers shall not extend more than 3mm beyond the surface of the plate. All welds shall have complete penetration and shall not contain detrimental imperfection. The back sides of the welds joints shall be chipped or flame gauged to sound metal before deposit weld metals to the back sides of the joints. Defects in welds shall be chipped or flame gauged until sound metal is reached in all sides and the resulting cavity shall be re-welded. The welding of temporary attachments to the pipeline sections for the purpose of handling or aligning of the section to each other, shall be limited to essential requirements subject to the approval of the Engineer- in-charge. All such attachments shall be removed by careful chipping by flame cutting and any damage to sections shall be repaired by welding, if required. All longitudinal and shop circumferential welds in the pipe shells and for the ends of stiffener rings shall be of double welded butt joints or single welded butt joints, whereas field circumferential welds shall be single welded butt joints with backing up strips. When single welded butt joints are used, the root of the welds shall then be deposited to obtain full penetration. After welding is completed all weld shall then be deposited to obtain full penetration. After welding is completed all weld spatter shall be removed by grinding. All welding shall be performed under cover and pipeline sections to welded shall be protected from the direct rays of the sun. All welds which fail to pass non-destructive tests described in para 19.10.5 shall be made on all welds which have been thus prepared. As far as practicable, all welding between dissimilar thickness shall be done in the shops. Where the thickness of pipe varies, the difference in thickness of pipes shall be restricted to 5mm. The internal diameter shall be kept the same at such junction. 21.10.2 WELDING PROCEDURES The specifications of each welding/welding procedure that has to be followed in construction shall be recorded in details by the Contractor. Such procedure shall be qualified in accordance with latest practices, and shall conform to IS: 823 – 1964 and IS : 4353 -1976. 21.10.3 QUALIFICATION OF WELDERS All welders assigned to manual welding shall have successfully passed the tests prescribed for welder qualification as per IS : 1181 and IS : 817. If in the opinion of the Engineer-in-charge or his representative, the work of any welding operator becomes/appears questionable, such operator shall be required to pass another qualification test. The Contractor shall supply materials, equipment, apparatus and labour required for making the above tests. 21.10.4 NON-DESTRUCTIVE TESTS Wherever welded butt joints are used for the joints for the pipe course or expansion joints, these will be subjected to Radiographic test for full length. All longitudinal joints and circumferential shop joints shall be subjected to 100% Radiographic examination and circumferential field joints are subjected to 100% ultrasonic examination. The procedure for the radiographic examination, the acceptable standards of welds, the repair of defective welds and the re-examination of repaired welds shall conform to IS : 1182 or relevant sections of ASME code. The costs of weld tests and radiographic examination shall be borne by the Contractor. Prior to making the radiographs identification marks adjacent to the welds, such marks shall be so designed and located that the images will appear in radiographs. The mark shall be painted, stamped or fastened to the shells as directed by the Engineer-in- charge. All X-Ray films of the welded joints shall become the property of the Employer and shall be forwarded (properly identified) to Engineer-in-charge. Radiography by X- Ray may be replaced by Gamma-ray method using either cobalt 60; iridium 192 or ceasium 137. 21.10.5 TEST DURING FABRICATION AND ERECTION The Contractor shall carry out the following tests on each pipe and weld joints individually. a) Hydrostatic Test Each section of the steel pipeline (including bends fabricated for field erection) shall be tested under hydraulic pressure equal to 1.5 times design pressure. However pressure for hydrostatic tests, shall not exceed the pressure computed by the following formula. Straight pipes and bends: Yp x T P = ----------- R 2 P- test pressure in N/mm . Yp -Yield point stress of steel used in the particular course under test 2 in N/mm T- actual minimum wall thickness of pipe in mm in the pipe length tested. R- Internal Radius of pipe in mm. Each pipe shall be completely filled with water and the pressure shall be slowly and uniformly increased until the required test pressure is reached. The test pressure shall be applied and released three times successively and after each application shall be held steady, for at least 15 minutes or till such time until all welded joint and plate can be examined for defects, leaks etc. Any defects in welds or plates disclosed by the hydrostatic test shall be repaired by the Contractor to the satisfaction of the Engineer –in- charge. All repaired sections shall be again tested hydro-statically. b) Leakage Test: This will be conducted by filling the pipeline with water from intake with the suitable type of valves in the pump house closed. All the field joints and the expansion joints gland packing shall be tightened with in permissible limits. If necessary, measures to prevent leakage at other location will be taken by the Contractor. 21.11 PAINTING 21.11.1 GENERAL: All steel liner assemblies shall be cleaned and painted as hereinafter specified. Machined surfaces and screw threads to be in rolling or sliding contract shall be shop coated with a rust preventive compound before transportation. Outside surface of ferrules to be erected in the tunnels and in anchor blocks shall be painted in shop with cement solution. Out side surfaces of other ferrules for over ground lines shall be painted with cold applied coat tar epoxy paint. Inside surface shall be coated in shop with zinc rich epoxy primer and cold applied, coal tar epoxy paint. Completed coatings shall, in all respects, conform to the detailed requirements of these specifications. 21.11.2 PAINTING SCHEDULE: Cleaning and Painting of steel liner shall be done in accordance with following schedule. Total No. of Paints or Coating Dry film thickness Item coats (in materials of paint coats shop or field) i) External Coat of Cement solution surfaces whichare mixed with 5% potassium 1 embedded in dichromat Concrete ii) Exposed Cold applied coat far surface of liners epoxy paint above the ground a) Zinc Rich epoxy primer Each Coat minimum 2 of 50 microns b) Cold applied coal tar 100 Microns epoxy paint 3 minimum for each coat iii) Inter on Cold applied tar epoxy surfaces paint a) Zinc Rich epoxy primer Each Coat minimum 2 of 50 microns b) Cold applied coal tar 100 Microns epoxy paint 3 minimum for each coat 21.11.3 PREPARATION OF SURFACES FOR PAINTING Weld burrs or any other objectionable irregularities shall be carefully removed or repaired by suitable means before cleaning. Any frit or dust remaining from the cleaning operation shall be completely removed from the surfaces by brushing, air blowing, suction or other effective means before the surfaces are accepted for painting. In the event of rust formation or when the surfaces become otherwise contaminated in the interval between cleaning and painting, re-cleaning shall be required to be done. Surface preparation shall be in accordance with the method given below. All oil, grease and dirt shall be removed from the surface by the use of clean mineral spirits, or white gasoline followed by wiping with clean wiping materials, except that for surfaces, which require coal tar coatings, the cleaning solvent shall be. Following the solvent cleaning, the surface to be painted shall be cleaned to base metal to remove all rust mill scale and other tightly adhering objectionable foreign materials by san blasting or grit blasting. A clean, dry Gypsum and salt free quartz and having grain size 0.7 to 1.5mm shall be used for sand blasting. Blast cleaning shall be accomplished with effectively clean the metal and have roughened surface suitable for tenacious adhesion of subsequent coasting. The surfaces which have been thus cleaned shall be primed as soon as practicable after such preparation has been completed, but in any event prior to deterioration of the prepared surface. 21.11.4 APPLICATION PROCEDURE AND QUALITY CONTROL OF PAINTS Paint and coating materials to be applied shall be in a thoroughly mixed condition at the time of application and shall not be thinned except where hereinafter specifically provided. Paint shall not be applied when temperature of the steel surface to be painted is less than 3 degree C above the dew point or when the weather is frosty/foggy or when the relative humidity is enough to cause condensation on the surfaces to be painted. Paint shall be applied by air spraying or brushing. The Contractor shall make available on site/necessary/equipment to measure the thickness of painting coats. Suitable means shall be provided to prevent segregation during the painting operation. Each cost of paint shall cover completely and uniformly the surface being painted and shall be free from runs sags and blisters. Except as other wise specifically provided, each coat shall be allowed to dry or harden sufficiently before a succeeding coat is applied. 21.11.5 COVERAGE, APPLICATION AND PREPARATION OF VARIOUS PAINT MATERIALS SHALL BE AS FOLLOWS: a) Rust Preventive Compound: Rust preventive compound shall be applied by any convenient method which shall ensure coverage of the surface with a heavy uniform coating not less than 0.4mm thick. b) Cold Applied Coal Tar Epoxy Paint: The Contractor shall specifically furnish, brand name of paint and the details of the relevant specification or accepted Standard practice for application procedure. Primer drying time before first coat of epoxy paint can be given shall be indicated. Similarly, drying time between each successive coat of epoxy paint and its final curing time for a well bonded film as recommended by the manufacturer of paint shall be indicated Quality/life of this paint after application shall not deteriorate at any ambient temperature form 5 degree C to 75 degree C. c) Zinc Rich Epoxy Primer: The zinc rich primer shall be applied in two coats by brush or by spray over sand blasted surface. The zinc rich primer shall be stirred properly at regular intervals during applications. Thinning of zinc paste shall be permitted but only with suitable fluid, as directed by the Engineer-in-Charge. The addition of suspension fluid shall not exceed 15 percent. The second and subsequent coasts of primer shall not be applied earlier than 24 hours after the application of previous coat. 21.11.6 CLEANING AND REPAIR OF SHOP PAINTED SURFACES: Metal works painted in shop or field shall be handled with care so as to preserve the coatings in best practicable condition. Before proceeding with the regular painting or coating operation, the Contractor shall clean and repair all areas of shop coat which are defective or damaged areas that are loose, weekly bonded, blistered, rusted or otherwise defective shall be removed to clean metal by scraping, chipping, power wire brushing or other effective means. Areas, thus prepared shall be cleaned of all dust, dirt and other contamination using cleaned of all dust, dirt and other contamination using clean rug and clean solvent. These surfaces shall then be repainted in accordance with the painting schedule and shall be required to pass acceptance tests as specified. 21.12 TRANSPORTATION: 21.12.1 DESPATCH AND TRANSPORTATION The transportation of the fabricated shells and accessories from the Fabrication work shop to the site of erection shall be started only after obtaining approval of the Engineer- in-Charge. The safe transport and handling of the steel plates from fabrication workshop to the work site shall be done by the Contractor. He shall deploy suitable transportation and handling equipment such as trailers, lorries, loading and unloading hoists, winches, rails steel rope, jacks, etc., The Contractor shall include and provide for spiders, saddles, or supports, etc, for securely fastening and protecting the steel liner assemblies in transit so as to avoid any damage to the liner or to the paint done in shop. The Contractor shall be fully responsible for all loss and damage caused by or occasioned by any defect in handling or transportation. All exposed finished surfaces shall be adequately protected against abrasion during transport. Defects, if any, caused to the pipe courses or painting during transportation and handling shall be rectified by the Contractor to the satisfaction of the Engineer-in-Charge. 21.13 MATCH MARKING AND WEIGHT: Each part of the steel liner or other auxiliary assemblies shall be legibly marked to show their relative position in the finished marking on each assembly to show top of field/shop vertical, the direction of flow and the serial number shall be made with light steel stamps. The approximate weight of each piece or assembly to be dispatched shall be painted as well as indicated in tags attached to the assembly. A list of the weight of assemblies/components dispatched by the Contractor from shop to the site of erection shall be submitted to the Engineer-in-Charge simultaneously. 21.14 ERECTION 21.14.1 STEEL LINERS TO BE ERECTED IN THE TUNNEL SHAFTS (a) The steel liners shall be assembled and installed in place inside the tunnel accurately to line and grade as shown on the drawings and as directed by the Engineer-in-Charge. Rails required for formation of erection track will be procured by the Contractor and the Contractor has to erect these rails at his own cost. The tenderer has to quote his rates for erection of ferrules taking into consideration of erection charges of rails for formation of Erection track. (b) After successful erection of steel liner assembly/assemblies as per approved drawings, concreting and grouting etc., of steel liner shall be done before erection of next assembly is undertaken. (c) Any timber supports provided for supporting the steel liner shall be removed by the Contractor before concreting is undertaken and shall not be permitted to be embedded in concrete. (d) The Contractor shall deploy sufficient drew or skilled and unskilled workmen and equipment so that erection of liner and concreting are carried out simultaneously. 21.14.2 ERECTION PROCEDURE (i) Rail Track The Contractor shall preferably install and maintain a rail track to move and to position the pipe sections and leave the rails embedded in secondary concrete with the approval of Engineer-in-Charge, provided the rails are supported on steel pieces. Finger bars and other temporary supports shall be installed in such a way that no deformations are induced on the pipe. (ii) Alignment and Welding a) The steel liner shall be installed on site in correct grade and ligament. b) The responsibility for accurate alignment and erection of shells and bends with reference to the control points rests with the Contractor. c) Any defects in the alignment of the steel liner shall be rectified by the Contractor. d) Sufficient finger bars shall be used on circumferential joints to maintain the alignment during the welding operation. e) No track welding shall be allowed in case of pressure vessel quality, high strength quenched and tempered steel. Field welding inside the steel liner shall be done with back up strip on the outer surface at f) the joint. 21.14.3 TOLERANCES: The tolerances in the alignment and shape of the erected steel liner shall be as mentioned below or specified in other acceptable international standards. a) Out of straightness of the shell shall be less than 2L/1000 for the total cylindrical length. b) The difference between the maximum and the minimum diameter at any cross section of the erected Cylindrical length shall be within the limits specified in para 220.127.116.11(d) hereof. c) For single welded butt joint with backing strip and double welded butt joint with double „V‟, the minimum separation of edges of shells to be welded shall not exceed 10mm and 3mm respectively unless otherwise directed by the Engineer-in-Charge. d) Cleaning and Painting in the Field: After erection, concrete back filling and grouting, all temporary fixtures/ appurtenances, debris etc., inside the steel liner shall be carefully removed. Atleast 200mm wide strip of pipe along the field welded joints shall be thoroughly cleaned before painting. The same treatment shall be required at the spots where bars or other temporary steel pieces were installed to facilitate erection of steel liners. The entire interior surfaces of steel liner shall be cleaned and painted as per specifications laid down hereof. ANNEXURE - AC 01 PUMP HOUSE 1. Size of pump house 2. Bottom level of pump house 3. Shot creting details 4. Side lining thickness and specification 5. Bed concrete thickness and specification 6. Foundation concrete of pumps a) Primary concrete - Specification, quantity, reinforcement details b) Secondary concrete - Specification, quantity, reinforcement detail 7. Details of specifications of columns for EOT crane a) Specification b) Number of columns c) Span width 8. Pump roof details 9. Annexe details a) Number of annexeies considered b) Dimensions of annexe c) Floor concrete - thickness, specification and quantity. 10. Details of lift proposed 11. Details of stair case proposed 12. Service bay size, details of floor concrete 13. Details of flooring in pump house, annexies and other areas. 14. Other details if any ANNEXURE – AC 02 PRESSURE MAINS 1. Diameter of Pressure main proposed 2. Length of Pressure mains 3. Thickness and specification of steel plates for Pressure mains 4. Total length of Pressure mains on the ground 5. Details of anchor/Thrust blocks a) Number of blocks and Location b) Size of blocks c) Specification of concrete d) Quantity of concrete e) Reinforcement quantity f) Pedestals details 6. Number of expansion joints 7. Number of rockers and rock pins 8. Concrete specification and quantity to be laid all around the delivery mains in the inclined tunnel shaft 9. Other details if any ANNEXURE – AC 03 CISTERN 1. Size of Cistern well 2. Details of side walls 3. Details of centre walls 4. Details of weir 5. Details of down stream apron and protection works 6. Concrete quantity specification wise 7. Other details if any ANNEXURE - AC 04 TUNNEL 2. Length of Tunnel proposed 3. Diameter of the Tunnel proposed 4. Slope of ramp considered at the entrance portal of Tunnel and its excavation quantity 5. Excavation quantity of Main Tunnel a) All soils b) HDR c) F&F d) Hard Rock 6. Specification of Lining Concrete proposed 7. Thickness of Concrete Lining 8. Concrete quantity 9. Location & Length of Adit Tunnel 10. Adit Tunnel excavation quantity 11. Quantity of Steel reinforcement if RCC lining is proposed 12. Intake Structure a) Details of Concrete proposed for various parts of intake structure. b) Details of Gates proposed for intake structures ANNEXURE – AC 05 MISCELLANEOUS CIVIL WORKS 1. Details of Drilling and Grouting in rock ledge. a) Drill hole size b) Number of rows proposed c) Distance between each row proposed d) Maximum depth of drilling grouting e) Drilling quantity f) Grouting quantity and specification 2. Any other items considered by Bidder ADDENDUM - 2 ANNEXURE - I MILE STONE PROGRAMME Name of Work : PRANAHITA-CHEVELLA LIFT IRRIGATION SCHEME – LINK- II - PACKAGE- 8– Detailed Investigation , Designs and Execution of Lift Irrigation Scheme for drawl and lifting of 114.24 TMC of water from Ragampet (V),near Kakatiya Canal, Choppadandi (M), Karimnagar District to Motevagu Reservoir and Carrying by a Gravity Canal to existing Flood Flow Canal to feed Mid Manair Reservoir with the Components such as Lined Gravity Canal, CM & CD Works, Lift, Pressure mains and Lined Tunnels with all associated Civil, Hydro-Mechanical and Electro-Mechanical works. Mile Financial Stone Period Description of Item (in Overall No. Percentage) 1 2 3 4 Detailed investigation , Soil exploration, designs, 3 1 preparation of land plan schedules etc., for all 0.16 months components of works and its approval. Detailed investigation , Soil exploration, designs, 3 preparation of land plan schedules etc., for all 2 1.00 months components of works and its approval, Execution of Tunnel. 3 Execution of Lined Gravity Canal and CD & CM works, 3 2.00 months Tunnel works 3 Execution of Lined Gravity Canal and CD & CM works 4 3.00 months and Execution of Tunnel works Execution of Lined Gravity Canal and CD & CM works 3 5 ,Execution of Tunnel works, Surge pool, and Pump 4.00 months house. Execution of Lined Gravity Canal and CD & CM works 3 6 ,Execution of Tunnel works, Surge pool, and Pump 6.00 months house, . Execution of Lined Gravity Canal and CD & CM works 3 7 ,Execution of Tunnel works, Surge pool, and Pump 6.00 months house, . Execution of Lined Gravity Canal and CD & CM works 3 8 ,Execution of Tunnel works, Surge pool, Pump house, 6.00 months and Cistern Execution of Tunnel works, Execution of Lined Gravity 3 9 Canal and CD & CM works, Surge pool, Pump house, 7.00 months Cistern. 3 Execution of Tunnel works, Surge pool, Pump house, 10 7.00 months Cistern and Lined Lead Channel. 3 Execution of Tunnel works, Surge pool, Pump house, 11 7.00 months Cistern and lined Lead channel and its Structures. Execution of Tunnel works, Surge pool, Reservoir, Pump 3 12 house, Cistern and lined Lead channel and its Structures 8.00 months . Execution of Tunnel works, Surge pool, Pump house, 3 Cistern, Hydro Mechanical works, delivery mains, 13 8.90 months Electro-Mechanical works (pumps & Motors)and lined lead channel and its structures. 3 Execution of Hydro Mechanical works, Delivery Mains 14 9.00 months and Electro-Mechanical works (Pumps & Motors) Execution of Hydro Mechanical works, Delivery Mains, 3 15 Electro-Mechanical works (Pumps & Motors) and other 9.00 months civil works. Execution of Hydro Mechanical works, Delivery Mains 3 16 Electro-Mechanical works (Pumps & Motors), and other 7.00 months Civil works. TOTAL( %) 91.06 The Mile Stone pogramme is tentative and will be revised after NOTE : furnishing the Estimate and Mile Stone programme by the Agency. ADDENDUM - 3 ANNEXURE - II SCHEDULE OF PAYMENT Name of Work : PRANAHITA-CHEVELLA LIFT IRRIGATION SCHEME – LINK- II - PACKAGE- 8–Detailed Investigation , Designs and Execution of Lift Irrigation Scheme for drawl and lifting of 114.24 TMC of water from Ragampet (V),near Kakatiya Canal, Choppadandi (M), Karimnagar District to Motevagu Reservoir and Carrying by a Gravity Canal to existing Flood Flow Canal to feed Mid Manair Reservoir with the Components such as Lined Gravity Canal, CM & CD Works, Lift, Pressure mains and Lined Tunnels with all associated Civil, Hydro-Mechanical and Electro-Mechanical works. Sl.No. Description of Item % of Bid Amount 1 2 3 Excavation of Tunnel, Adits, Surge pool and Draft tube 1 20.48 Tunnels with all other associated works including Lining Excavation of Gravity Channel, Construction of CM & CD 2 3.20 works, Head Regulator, etc., Lift works such as Pump House, Pumps, Motors, Hydro- 3 Mechanical, Electro-Mechanical, Delivery mains, anchor 60.58 blocks, Delivery Cistern and all other associated works. Miscellaneous works, Investigation, Design, Drawings etc. 4 6.80 and Taxes & Duties etc., Operation and Maintenance of Civil works for a period of 5 ( 5 8.94 Five ) years and HM & EM works for 15 (Fifteen) years GRAND TOTAL 100.00 1. The above Schedule is subject to Clause No.41.2.4 and NOTE: 42 of Conditions of Contract. 2. The Payment Schedule is tentative. Payment Schedule shall be revised after furnishing the working Estimate and Component wise cost by the Agency. Note:- This Corrigendum No.6 is applicable to the above referred items only and other conditions remains same. Sd/28-05-2008 Superintending Engineer, I&CADD. Sripada Yellampally Project Circle, Mancherial, Adilabad Dist.
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