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					                              TECHNIQE IN PLANNING AND PRE-
Highway Engineering            CONSTRUCTION OF ROAD WORK       C3010 / UNIT2


i

        UNIT 2



    TECHNIQUE IN PLANNING AND PRE-CONSTRUCTION
                              OF ROADWORK




                                   OBJECTIVES




General Objective

To understand the planning activities and all pre-construction works

Specific Objectives

At the end of the unit you should be able to :-

       describe the planning objective.
       state the procedures to identify a new road.
       state the procedures for site investigation
       describe the method of site exploration.
       describe the survey works.
                             TECHNIQE IN PLANNING AND PRE-
Highway Engineering           CONSTRUCTION OF ROAD WORK          C3010 / UNIT2




                                      TECHNIQUE IN PLANNING AND
                                      PRE-CONSTRUCTION
                                      ROADWORKS




2.0   TECHNIQUES IN PLANNING AND PRE-CONSTRUCTION
      ROADWORK.


      A construction of a new road must under go an extensive planning,
      accurate land surveying and economic planning.


      2.0.1 Planning Requirements


            A modern highway construction would include:-
         1. A collection of a tabulated information on the existing transportation
            facilities in the area.
         2. The determination of the general inter-relation of all branches of the
            transportation system and their effect on each other.
         3. The determination of the adequacy or otherwise of the existing
            facilities as per present needs and the improvement and extension
            of these facilities for anticipated future needs for a certain period.
         4. Methods of financing the projects and the duration of the
            construction.
         5. An estimation of construction and maintenance.
                           TECHNIQE IN PLANNING AND PRE-
Highway Engineering         CONSTRUCTION OF ROAD WORK         C3010 / UNIT2




        Any highway planning study can be sub-divided into :-
           1. Road inventory study.
           2. Traffic studies.
           3. Economic planning studies.
           4. Financial planning studies.


     2.0.2 Preparation and Planning Scheme of a New Road.


                  Planning expertise, evaluation on survey work, knowledge
           on geology and experience on civil engineering area are essentially
           needed in constructing of a new road. The traffic needs, the
           purpose on planning at certain route and approximate cost thus
           become very vital information to be considered before constructing
           a new road.


                  The synopsis of procedures that is used for identifying,
           planning and constructing a new road are listed in the following
           page. However, not all new roads follow these procedures. Some of
           the procedures are valid for certain terms and conditions only.


                  Below is set of procedure that is used for identifying,
           planning and constructing a new road. The procedures are;


           1. Identify the problem in traffic congestion, accident and
              environment by making a research on transportation and
              problematic areas.
           2. Identify the maintenance and new construction work needed.
           3. Identify the organization and Ministries that are responsible with
              the construction work such as JKR, TNB etc.
                            TECHNIQE IN PLANNING AND PRE-
Highway Engineering          CONSTRUCTION OF ROAD WORK         C3010 / UNIT2


           4. Collect the information for briefing.
           5. Prepare the following plans: -
                  a. Topography plan.
                  b. Usage land plan.
                  c. Geology plan.
                  d. Agriculture area plan.
                  e. Domestic plan.
                  f. Traffic flow plan.
                  g. Town Consult planning document.


           6. Draw a temporary layout sketch and include related
              suggestion.
           7. Get information on;
                  a. Junctions.
                  b. River and drainage.
                  c. Survey information.
                  d. The latest traffic data.
                  e. Ground Level.
           8. Prepare a detailed layout with consideration to environmental
              impact.
           9. Make a valuation.
           10. Choose the best road to be constructed. However, the
              alternative road should be equally prepared in the planning.
           11. Negotiate with other related group such as :-
                  a. Ministry of Science and Environment.
                  b. Ministry of Transportation.
                  c. Water Board, Forestry Department, Telecom Company
                  d. National Museum.
                  e. Railway Station.
                  f. Geology and Mineral Department.
           12. Present a report on the entire technical problems.
                           TECHNIQE IN PLANNING AND PRE-
Highway Engineering         CONSTRUCTION OF ROAD WORK           C3010 / UNIT2


           13. Analyze the problems faced by the public.
           14. Prepare the preliminary report based on the above information
               and submit it to the planning division.
           15. Wait for the outcome or result.
                  a. If it is acceptable, draw a road design at 1 : 2500 scale
                      and proceed to the particular ministry.
                  b. If it is unacceptable, it needs to be revised thoroughly or
                      it will be cancelled.
           16. Proceed with the following: -
                  a. Start planning the main task (the identified road).
                  b. Start planning the alternative roads.
                  c. Start purchasing the important materials.
           17. Get the information from the public on the suggested road and
               the other roads involved. Set a panel that consists of external
               lawyers and other professionals to conduct a survey.
           18. Submit the report to the respective Ministry and wait for the
               approval.
           19. Prepare the financial report based on the cost benefit analysis
               to determine the advantages will bring to the public.
           20. Advertise a tender notice and the selected contractor will then
               need to prepare and submit the quotation of the contract plan
               and document.
           21. Accept the tender and start the construction work.


     There are 3 stages in planning the construction of a new road :-


             1. Stage 1 - Prepare a preliminary report.
             2. Stage 2 - Submit the preliminary report.
             3. Stage 3 - Finalize the report.
                           TECHNIQE IN PLANNING AND PRE-
Highway Engineering         CONSTRUCTION OF ROAD WORK          C3010 / UNIT2




     2.0.3 Stage 1- Preparing a preliminary report.


                  In this stage, it includes all the preliminary reports and
           information that are received during the ensuing stage (refer to
           2.0.2, Procedure 14). They are: -
                  a. Traffic surveying work.
                  b. Evaluation on the information and planning. Consider
                      suggestion if there is another useful choice.
                  c. Design using 6” : 1 mile scale.
                  d. Budget of the construction and its advantages.
                  e. Identify the certain road.
                  f. Report on the alternative road, which includes the
                      topography, geology and traffic flow, soil consuming and
                      historical places.
                  g. Obtain cooperation from the related group such as town
                      council and state government.
                  h. If the project is over budgeted the ministry must be inform
                      and no further work shall be proceed.


     2.0.4 Stage 2 - Submitting the preliminary report.


                In the preliminary report, it explains about the proposal and its
           alternatives of the identified project. It then is submitted to the
           person in-charged to obtain permission. However, the following
           questions need to be considered.


                  a. Are the suggestions fulfilled the planning needs at the
                      national level.
                  b. Are the advantages accepted?
                           TECHNIQE IN PLANNING AND PRE-
Highway Engineering         CONSTRUCTION OF ROAD WORK          C3010 / UNIT2


                  c. Are the suggested solution accepted in term of political or
                      environmental aspect.


           While the preliminary report is being studied further, other
           experiments should be done such as:-


                  a. Further soil investigation.
                  b. The plan preparation on the new road and other related
                      roads. Report and work are to be prepared. It will only be
                      submitted if the preliminary report is accepted.


     2.0.5 Stage 3 - Finalizing the Report


                  a. When the preliminary report is accepted, prepare the
                      road plan with 1:2500 scale.
                  b. When the final report is completed, submit it to the Head
                      Quarter for approval. Here, a right budget and
                      advantages of the project shall be included for approval
                      purposes.
                  c. After the costing and advantages valuation are done, this
                      final report will be submitted to the responsible person to
                      start off the construction work.
                  d. If there is no protest from the public or other parties in
                      fact, the tender will be offered and the selected
                      contractor. Then, all the construction works will start.
                  e. If there is a protest, a committee member will be set up
                      for further investigation.
                             TECHNIQE IN PLANNING AND PRE-
Highway Engineering           CONSTRUCTION OF ROAD WORK        C3010 / UNIT2




     2.0.6 The content of the Preliminary Report


           The preliminary report which includes the plan must contain the
           following aspects:-
                 a. The existence situation – which is on physical shape and
                      scheme objective of the existence road.
                 b. The traffic situation – based on the latest data (not more
                      than 3 years). A report should include content the total of
                      traffic user.
                 c. The alternative roads, which include the costing,
                      advantages and the environmental impact.
                 d. Road classification – identify the road classification that is
                      to be built; highway or ordinary road.
                 e. Negotiation on the report and the result.
                 f. Budget the total of roadwork cost, bridges work and
                      earthwork approximately 20% from the previous budget.
                      The cost report should comprise the following:
                      Roadwork:-
                         -    Site clearing cost.
                         -    Earthwork cost.
                         -    Pavement construction and road shoulder work
                              cost.
                         -    Road furniture work.
                         -    Facilities service work.
                         -    Contingency stretch cost.


                 g. Valuation is to see the economical aspect of the project.
                           TECHNIQE IN PLANNING AND PRE-
Highway Engineering         CONSTRUCTION OF ROAD WORK         C3010 / UNIT2


                 h. Enclosed plans – plan with 6”:1 mile scale is used for
                      new scheme. For the city or village area a bigger scale is
                      used. Plan must show the following:-
                         a. The plan of the approved alternative roads.
                         b. The type of junction and its location.


                 Avoid using the existence plan. Beside the, the activities
                 which would be included in the planning and pre-
                 construction road work are as follow:


              1. Site investigation.
              2. Survey works and setting out.
              3. Site clearing and top soil deletions.
              4. Earth works.
                           TECHNIQE IN PLANNING AND PRE-
Highway Engineering         CONSTRUCTION OF ROAD WORK         C3010 / UNIT2




                                ACTIVITY 2 A




TEST YOUR UNDERSTANDING BEFORE YOU CONTINUE WITH THE NEXT
INPUT

 Question

  1. State the planning objective of planning in executing a new road
     development.




  2. State four other activities in planning and pre-construction roadworks.


        a.
        b.
        c.
        d.
                           TECHNIQE IN PLANNING AND PRE-
Highway Engineering         CONSTRUCTION OF ROAD WORK        C3010 / UNIT2




                                    FEEDBACK ON
                                     ACTIVITY 2 A


    Answer

     1.    The objective of planning is to provide a highway system which
           would give maximum transportation facilities at a minimum cost.


     2.    The other activities in planning and pre-construction roadworks be
           as follows :


                  1. Site investigation.
                  2. Survey works and setting out.
                  3. Site clearing and top soil deletions.
                  4. Earth works.
                             TECHNIQE IN PLANNING AND PRE-
Highway Engineering           CONSTRUCTION OF ROAD WORK           C3010 / UNIT2




2.1    SITE INVESTIGATION


            Road structures are the structure which is supported by the ground.
      The interaction between the structure and the soil beneath it is complex,
      and therefore knowledge of the site and soil condition is important.


      2.1.1 Procedures of the investigation


            2.1.1.1 Compact sites


                           In the case of compact sites for road structure, the
                      investigation requires deep and closely speed borings. The
                      actual number and position of borings depend on the types
                      of structure and nature of sites. However, the number of
                      bore hole should be such as to given a clear picture of all
                      significant variations in the soil over the site, and the depth
                      of such bore hole should be such as to reach all strata
                      likely to influence the stability of the works.


            2.1.1.2 Method of site exploration


                           When discussing the procedure of the investigation,
                      reference is made to borings as a means of the
                      investigation. This is perhaps it is the most common
                      method of site exploration, but certainly not the only one.
                      Considering new works, from the very small to the very
                      large contract, a general guide to exploration would be as
                      follows:
                         1. Small works- trial pits up to 3m deep.
                         TECHNIQE IN PLANNING AND PRE-
Highway Engineering       CONSTRUCTION OF ROAD WORK           C3010 / UNIT2


                      2. Medium to large scale works – borings up to 30m
                         deep
                      3. Very large scale works – a combination of deep
                         boring, pits and insitu examination from heading and
                         shafts.


                        It must be noted that the above is only guide: the
                 detailed methods of exploration would depend on the types
                 of the construction and the site involved.




                 a. Trial pits


                        This is the cheapest form of exploration in shallow
                 depth; above 3 m deep the cost increases rapidly compared
                 with boring. The main advantage is that soils and rocks can
                 be exposed and examined insitu. This method shows
                 changes in strata much more clearly than by boring. The pits
                 are dug out either by local labour or by a small tractor
                 mounted excavator. The plan size of a pits depends on
                 method of excavation, but approximately 1.2 x 1.2 m and
                 should be dug at distances 20m apart in either direction.


                        Problem occurs in water bearing soils, particularly
                 sands, and therefore the economies of shoring and pumping
                 pits may outweigh the savings gained against specialist
                 borings. In dry condition these pits are particularly valuable
                 since they allow hand cut sample to be taken, thereby
                 minimizing the disturbance of the sample and maximizing
                 the condition for accurate testing. Deeper trial pits maybe
                 used for investigation of rock fissures or to explore layer of
                          TECHNIQE IN PLANNING AND PRE-
Highway Engineering        CONSTRUCTION OF ROAD WORK          C3010 / UNIT2


                 weak rock which cannot be removed intact in normal boring
                 operations. Such deep pits are costly to construct and would
                 be used only a large scale exploration. Trial pits are the best
                 method of exploring back filled areas and side overlain by
                 variable natural deposit.




                 b. Borings


                        All boring should be should be spaced sufficiently
                 closed together to prevent false deduction concerning the
                 uniformity of horizontal strata. The deeps of boring will be
                 determined by the type of loading involved but account must
                 be taken of any slope in the strata and variation in their
                 thickness. In particular, when boring through glacial
                 deposits, care must be exercised to insure that borders are
                 not mistaken for bedrock.


                        There are three main factors which govern the depth
                 of exploration:
                 1. The depth to which the soil is to be significantly stressed.
                 2. The depth to which weathering is likely to affect the soil.
                 3. The depth at which impermeable strata occur.


                 c. Wash Borings.


                        The soil is loosened and removes from the bore hole
                 by mean of a strong jet of water or drilling mud. The liquid is
                 jetted through a steel tube which is work up and down the
                 hole. The liquid disintegrates the soil and carries it up the
                 annular space between the tube and casing. Wash boring as
                           TECHNIQE IN PLANNING AND PRE-
Highway Engineering         CONSTRUCTION OF ROAD WORK           C3010 / UNIT2


                  the advantage that the soil is not disturbed by blows of a tool
                  or shell, but it is limited to soil which do not contain boulders
                  or large gravels. Mud such as bentonite, allows boring to be
                  carried out without linings is non-cohesive soils. The soil in it
                  settled-out state can be dried and use for identification
                  purposes.


2.2   SURVEY WORK AND SETTING OUT


      2.2.1 Preliminary Survey


                  The preliminary survey consist in running a accurate
           traverse line, usually called the Base Line along the route already
           recommended as a result of reconnaissance survey, in order to
           obtain sufficient data for final location. Similar traverses may also
           be run along the secondary routes, if any. The preliminary survey
           shall help gather all the physical information which might affect the
           final location of the highway. The traverse being an “Open” one,
           adjustment cannot be made as in the case of closed traverse so
           that in order to ensure some standard of accuracy, certain
           precaution especially in the measurement of angels and chaining,
           etc., are necessary.


                  After establishing the Base Line, important topographical
           features may also be recorded. These features include swamps,
           lakes and any other features which affect the final location and
           design of the highway. All the information collected by preliminary
           survey work is used in preparing a map, often called the basic plan
           or Preliminary Survey Plan.
                           TECHNIQE IN PLANNING AND PRE-
Highway Engineering         CONSTRUCTION OF ROAD WORK           C3010 / UNIT2


                  The next step after recording all the available details on the
           basic plan is to locate the center line of the proposed highway on it.
           A number of trial lines are drawn on the plan, avoiding valuable
           property, obstruction and difficult areas such as water-logged
           areas, etc. Having thus selected the center-line on the plan, the
           next step consist in transferring on to the field.




     2.2.2 Setting Out


                  The first task is to establish a Base Line from which the
           whole of the road can be set out. The position of this line must be
           clearly marked on-site so that it can be re-established at any time.
           Setting out was done by plotting the construction boundaries after
           being referred from the previous survey on Preliminary Survey Plan
           and Base Line. Wooden pact shall be placed at each reference
           point and can be easily seen.
                           TECHNIQE IN PLANNING AND PRE-
Highway Engineering         CONSTRUCTION OF ROAD WORK           C3010 / UNIT2




                                  ACTIVITY 2 B




TEST YOUR UNDERSTANDING BEFORE YOU CONTINUE WITH THE NEXT
INPUT

 Question 1
  1. State the two methods that are used in soil exploration.
        a. ________________________________
        b. ________________________________


  2. State the three main factors which govern the depth of exploration.
        a. _________________________________
        b. _________________________________
        c. _________________________________
                           TECHNIQE IN PLANNING AND PRE-
Highway Engineering         CONSTRUCTION OF ROAD WORK        C3010 / UNIT2




                                   FEEDBACK ON
                                    ACTIVITY 2 B


     Answer

           1.    a. Trial pits
                 b. Borings


           2.    There are three main factors which govern the depth of
                 exploration:
                        1. The depth to which the soil is to be significantly
                            stressed.
                        2. The depth to which weathering is likely to affect
                            the soil.
                        3. The depth at which impermeable strata occur.
                            TECHNIQE IN PLANNING AND PRE-
Highway Engineering          CONSTRUCTION OF ROAD WORK      C3010 / UNIT2




  Question
     1. What are the procedures in identifying the construction of a new road.
     2. Describe the following aspects: -
                   a. Preliminary Survey.
                   b. Setting Out


     3. Describe the Trial Pits of soil exploration.
                           TECHNIQE IN PLANNING AND PRE-
Highway Engineering         CONSTRUCTION OF ROAD WORK          C3010 / UNIT2




    Answer

     The procedures to identify a new road include:-




     2a.   Preliminary Survey


                  The preliminary survey consist in running a accurate
           traverse line, usually called the Base Line along the route already
           recommended as a result of reconnaissance survey, in order to
           obtain sufficient data for final location. Similar traverses may also
           be run along the secondary routes, if any. The preliminary survey
           shall help gather all the physical information which might affect the
           final location of the highway. The traverse being an “Open” one,
           adjustment cannot be made as in the case of closed traverse so
           that in order to ensure some standard of accuracy, certain
           precaution especially in the measurement of angels and chaining,
           etc., are necessary.


                  After establishing the Base Line, important topographical
           features may also be recorded. These features include swamps,
           lakes and any other features which affect the final location and
           design of the highway. All the information collected by preliminary
                           TECHNIQE IN PLANNING AND PRE-
Highway Engineering         CONSTRUCTION OF ROAD WORK           C3010 / UNIT2


           survey work is used in preparing a map, often called the basic plan
           or Preliminary Survey Plan.


                  The next step after recording all the available details on the
           basic plan is to locate the center line of the proposed highway on it.
           A number of trial lines are drawn on the plan, avoiding valuable
           property, obstruction and difficult areas such as water-logged
           areas, etc. Having thus selected the center-line on the plan, the
           next step consist in transferring on to the field.
     2b.   Setting Out


                  The first task is to establish a Base Line from which the
           whole of the road can be set out. The position of this line must be
           clearly marked on-site so that it can be re-established at any time.
           Setting out was done by plotting the construction boundaries after
           being referred from the previous survey on Preliminary Survey Plan
           and Base Line. Wooden pact shall be placed at each reference
           point and can be easily seen.
           .


     3.    Trial pits


                  This is the cheapest form of exploration in shallow depth;
           above 3 m deep the cost increases rapidly compared with boring.
           The main advantage is that soils and rocks can be exposed and
           examined insitu. This method shows changes in strata much more
           clearly than by boring. The pits are dug out either by local labour or
           by a small tractor mounted excavator. The plan size of a pits
           depends on method of excavation, but approximately 1.2 x 1.2 m
           and should be dug at distances 20m apart in either direction. Trial
                          TECHNIQE IN PLANNING AND PRE-
Highway Engineering        CONSTRUCTION OF ROAD WORK         C3010 / UNIT2


           pits are the best method of exploring back filled areas and side
           overlain by variable natural deposit.

				
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