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ALUMINIUM FORMWORK SYSTEM

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					       (ALUMINIUM FORMWORK SYSTEM)

                              INDEX

Sr. No.                       Contents                             Page


   1      CHAPTER NO 1: Introduction                                1
   2      CHAPTER NO 2: What in an Aluminium Formwork?              4
                            1. Load action on formwork
   3      CHAPTER NO 3: Formwork Assembly                           7
   4      CHAPTER NO 4: Erecting Formwork for construction          9
                            1. Work cycle
                            2. Construction activity
   5      CHAPTER NO 5: Components of Aluminium Formwork            16
                            1. Beam Components
                            2. Deck Components
                            3. Wall Components
                            4. Other Components
                                                                          1.
   6      CHAPTER NO 6: Design of Formwork- Software Application    25
   7      CHAPTER NO 7: Advantages of Aluminium Formwork over       30
                          Conventional Formwork


   8      CHAPTER NO 8: Limitations                                 34
   9      CASE STUDY                                                35
  10        CONCLUSION                                                             37
  11        REFERENCES                                                             38




                                 CHAPTER NO:1
                                INTRODUCTION

                 Aluform is a construction system for forming cast in place concrete
structure of a Building. Aluform system provides aluminium formwork for RCC, load-
bearing ,multi-storeyed buildings and enables the walls and slab to be poured in the
same operation. This increases efficiency, and also produces an extra-ordinarily strong
structure with excellent concrete finish.
                 Due to the fine tolerances achieved in the machined metal formwork
components, consistent concrete shapes and finishes are obtained floor after floor,
building after building, confirming to the most exact standards of quality and accuracy.
This allows plumbing and electrical fittings to be prefabricated with the certain
knowledge that there will be an exact fit when assembled. The dimensional accuracy at
the concreted work also results in consistent fittings of doors and windows. The smooth
off form finish of the concrete eliminates the need for costly plastering.
                The system of Aluminium Forms has been used widely in the
construction of residential units in both low-rise & high-rise buildings. It has proven
to be very successful in the construction of mass housing projects in various parts of the
world. The system most suitable for Indian conditions is a tailor-made aluminium
formwork for cast-in-situ fully concrete structure. It is also a system for scheduling and
controlling the work of other connected construction trades such as steel reinforcement,
concrete placement and mechanical & electrical inserts.
                 The formwork system is unique because it enables the construction of
 the entire structure of a building in R.C.C. with all the members including walls, floor
 slabs, window hoods, balconies, sunken floors and various decorative features, being
 cast integrally for each floor as per the architect‟s requirement.


1.1 History of the Aluminium Formwork System :
      The Aluminium formwork system was developed by W.J. Malone, a Canadian
Engineer in the late 1970‟s as a system for constructing low-cost housing units in the
developing countries. The units were to be of cast in place concrete withthe loadbearing

walls and formed with aluminium panels. To be erected by the hundreds, using a
repetitive design, the system ensured a fast and economical method of construction.

         Using that fundamental concept 1200 units were built in Egypt followed by
  1500 units in Iraq. The latter project was incredibly successful-setting records for
speed and quality of construction at minimal costs.
          The Aluminium formwork system has been used successfully in different
 countries like Egypt, Hong Kong, India, Indonesia, Iraq, Malaysia, Philippines,
 Seychelles, Singapore, South Korea, Taiwan and Thailand.
1.2 Necessity of the Aluform System :
               The disparity between the supply and demand for affordable housing is
 tremendous. Rapid urbanization has resulted in a geometric increase in the housing
 demand, which cannot be fulfilled using conventional materials and methods of
 construction. The traditional or conventional method of construction for mass housing
 is comparatively, a slow process and has limited quality control, particularly when a
 large size project is involved. It is therefore obligatory to work out a method or a
 scheme where the speed and quality of construction are controlled automatically by a
 systematic approach. Therefore Aluminium Formwork System (AFS) identified to be
 suitable for Indian conditions for mass housing construction where quality and speed
 can be maintained at a reasonably high level .It is adoptable for any design of a
 building and establishes a kind of assembly line production.
              The methodology of using aluminium formwork takes in to consideration
 the important parameters namely the no. of housing units & the time that is available
 and works out the component of input as formwork. The whole structure is constructed
 with load bearing walls cast-in-situ by using pre-engineered aluminium forms with
 form-finished concrete and no plaster on any face.




                                   CHAPTER NO:2
                 WHAT IS AN ALUMINIUM FORMWORK?


         The panels of aluminium formwork are made from high strength aluminium
alloy, with the face or contact surface of the panel, made up of 4mm thick plate, which is
welded to a formwork of specially designed extruded sections, to form a robust
component. The panels are held in position by a simple pin and wedge arrangement
system that passes through holes in the outside rib of each panel. The panel fits precisely,
securely and requires no bracing. The walls are held together with high strength wall ties,
while the decks are supported by beams and props.
       Since the equipment is made of aluminium, it has sections that are large enough to
be effective, yet light enough in the weight to be handled by a single worker. Individual
workers can handle all the elements necessary for forming the system with no
requirement for heavy lifting equipment or skilled labor. By ensuring repetition of work
tasks on daily basis it is possible for the system to bring assembly line techniques to
construction site and to ensure quality work, by unskilled or semi-skilled workers.
       Trial erection of the formwork is carried out in factory conditions which ensure
that all components are correctly manufactured and no components are missed out. Also,
they are numbered and packed in such a manner so as to enable easy site erection and
dismantling.
 2.1 Loads acting on Aluminium formwork:
        In Construction, the formwork has to bear, besides its own weight, the weight of
wet concrete, the live load due to labor, and the impact due to pouring concrete and
workmen on it. The vibration caused due to vibrators used to compact the concrete
should also be taken care off. Thus, the design of the formwork is an essential part during
the construction of the building.
         In the design of planks and joists in bending & shear, a live load including the
impact may be taken as 370kg/m². It is however, usual to work with a small factor of
safety in the design of formwork. The surfaces of formwork should be dressed in such a
manner that after deflection due to weight of concrete and reinforcement, the surface
remains horizontal, or as desired by the designer. The sheathing with full live load of 370
kg/m² should not deflect more than 0.25 cm and the joists with 200kg/m² of live load
should not deflect more than 0.25cm.
       In the design of formwork for columns or walls, the hydrostatic pressure of the
concrete should be taken into account. This pressure depends upon the quantity of water
in the concrete, rate of pouring and the temperature.
       The hydrostatic pressure of the concrete increases with the following cases:-
        Increase in quantity of water in the mix.
        The smaller size of the aggregate.
        The lower temperature.
        The higher rate of pouring concrete.
       If the concrete is poured in layers at an interval such that concrete has time to set,
there will be very little chance of bulging.


       Alluminium as usual is not a very strong material. So the basic elements of the
formwork system are the panel which is a framework of extruded aluminium sections
welded to an aluminium sheet. It consists of high strength special aluminium
components. This produces a light weight panel with an excellent stiffness-to-weight
ratio, yielding minimal deflections when subjected to the load of weight concrete. The
panels are manufactured in standard sizes with non-standard elements produced to the
required size and size to suit the project requirements
This formwork is preferred because:-
i. In contrast to most of the modern construction systems, which are machine and
equipment oriented, the formwork does not depend upon heavy lifting equipment and can
be handled by unskilled labors.
ii. Fast construction is assured and is particularly suitable for large magnitude
construction of respective nature at one project site.
iii. Construction carried out by this system has exceptionally good quality with accurate
dimensions for all openings to receive windows and doors, right angles at meeting points
of wall to wall, wall to floor, wall to ceiling, etc, concrete surface finishes are good to
receive painting directly without plaster.
iv. System components are durable and can be used several times without sacrificing the
quality or correctness of dimensions and surface.
v. Monolithic construction of load bearing walls and slabs in concrete produces
structurally superior quality with very few constructions joined compared to the
conventional column and beam slabs construction combined with filter brick work or
block work subsequently covered by plaster.
vi. In view of the four – day cycle of casting the floor together with all slabs as against 14
to 20 – day cycle in the conventional method, completed RCC structure is available for
subsequent finish trades much faster, resulting in a saving of 10 to 15 days per floor in
the overall completion period.
vii. As all the walls are cast monolithic and simultaneously with floor slabs requiring no
further plasters finish. Therefore the time required in the conventional method for
construction of walls and plastering is saved.
viii. As fully completed structural frame is made available in one stretch for subsequent –
finishing items, uninterrupted progress can be planned ensuring, continuity in each trade,
thereby providing as cope for employing increased labor force on finishing item.
ix. As the system establishes a kind of “Assembly line production” phase – wise
completion in desired groups of buildings can be planned to achieve early utilization of
the buildings.
                               CHAPTER NO:3
                            FORMWORK ASSEMBLY

      All panels are clearly labeled to ensure that they are easily identifiable on site
and can be smoothly fitted together using the formwork modulation drawings. All
formwork begins at a corner and proceeds from there.
Fig No 1 : Wall Assembly Details
                              Fig No 2: Beam Assembly Details

Simplicity- Pin and Wedge System:

      The panels are held in position by a simple pin and wedge system that passes
through holes in the outside rib of each panel. The panels fit precisely, simply and
securely and require no bracing. Buildings can be constructed quickly and easily by
unskilled labour with hammer being the only tool required. Once the panels have been
numbered, measuring is not necessary. As the erection process is manually, tower cranes
are not required. The result is a typical 4 to 5 day cycle for floor – to – floor construction.
                                CHAPTER NO:4
            ERECTING FORMWORK FOR CONSTRUCTION


      The formwork is designed using the most economical assortment of panel sizes
with the help of the state-of-the art design software. The use of the software along with
the experience and skill of the designers ensures an efficient construction process by
incorporating the optimum assembly procedures, economical panel selection and
ultimately minimizing capital and operational costs.




                              Fig No 3:Erection of Platform
  Fig No 4: Striking of formwork




Fig No 5: Positioning of Platform
Fig No 5: Removal of Kicker
4.1.Work cycle:-

       The work at site hence follows a particular sequence. The work cycle begins with
the deshuttering of the panels. It takes about 12-15hrs. It is followed by positioning of the
brackets & platforms on the level. It takes about 10-15hrs simultaneously.
       The deshuttered panels are lifted & fixed on the floor .The activity requires 7-10
hours. Kicker & External shutters are fixed in 7 hrs. The wall shutters are erected in 6-8
hrs .One of the major activity reinforcement requires 10-12 hrs. The fixing of the
electrical conduits takes about 10 hrs and finally pouring of concrete takes place in these.
       This is a well synchronized work cycle for a period of 7 days. A period of 10-12
hrs is left after concreting for the concrete to gain strength before the beginning of the
next cycle. This work schedule has been planned for 1010-1080 sq m of formwork with
72-25cu m of concreting & approximate reinforcement.
       The formwork assembling at the site is a quick & easy process..All panels are
clearly labeled to ensure that they are easily identifiable on site and can be smoothly
fitted together using formwork modulation drawings. All formwork begins from corners
and proceeds from there.



The system usually follows a four day cycle: -


Day 1: -The first activity consists of erection of vertical reinforcement bars and one side
of the vertical formwork for the entire floor or a part of one floor.
Day 2: -The second activity involves erection of the second side of the vertical
formwork and formwork for the floor
Day 3: - Fixing reinforcement bars for floor slabs and casting of walls and slabs.
Day 4: -Removal of vertical form work panels after 24hours, leaving the props in place
for 7 days and floor slab formwork in place for 2.5 days.
4.2 Construction activitity:-
       The construction activities are divided as pre – concrete activities, during
concreting and post – concrete activities. They are as follows:


Pre-Concrete Activity:-
a) Receipt of Equipment on Site – The equipments is received in the site as ordered.
b) Level Surveys – Level checking are made to maintain horizontal level check.
c) Setting Out – The setting out of the formwork is done.
d) Control / Correction of Deviation – Deviation or any correction are carried out.
e) Erect Formwork – The formwork is erected on site.
f) Erect Deck Formwork – Deck is erected for labours to work.
g) Setting Kickers – kickers are provided over the beam.


       After the above activities have been completed it is necessary to check the
   following.
               All formwork should be cleaned and coated with approved realize agent.
               Ensure wall formwork is erected to the setting out lines.
               Check all openings are of correct dimensions, not twist.
               Check all horizontal formwork (deck soffit, and beam soffit etc.) in level.
               Ensure deck and beam props are vertical and there is vertical movement in
                the prop lengths.
               Check wall ties, pins and wedges are all in position and secure.
               Any surplus material or items to be cleared from the area to be cast.
               Ensure working platform brackets are securely fastened to the concrete.
On Concrete Activities:-
        At least two operatives should be on stand by during concreting for checking
pins, wedges and wall ties as the pour is in progress. Pins, wedges or wall ties missing
could lead to a movement of the formwork and possibility of the formwork being
damaged. This – effected area will then required remedial work after striking of the
formwork.


       Things to look for during concreting:

               Dislodging of pins / wedges due to vibration.

               Beam / deck props adjacent to drop areas slipping due to vibration.

               Ensure all bracing at special areas slipping due to vibration.

               Overspill of concrete at window opening etc.




Post- Concrete Activities:-
i) Strike Wall Form- It is required to strike down the wall form.
ii) Strike Deck Form- The deck form is then removed.
iii) Clean, Transport and stack formwork
iv) Strike Kicker Formwork – The kicker are removed.
v) Strike wall – Mounted on a Working Platform the wall are fitted on next floor.
vi) Erect Wall – Mount Working Platform and the wall is erected.
Normally all formwork can be struck after 12 hours.
   The post – concreting activities includes:
Cleaning:
   All components should be cleaned with scrapers and wire brushes as soon as they are
   struck. Wire brush is to be used on side rails only. The longer cleaning is delayed, the
   more difficult the task will be. It is usually best to clean panels in the area where they
   are struck.
Transporting:
There are basic three methods recommended when transporting to the next floor:
             The heaviest and the longest, which is a full height wall panel, can be
                 carried up the nearest stairway.
             Passes through void areas.
             Rose through slots specially formed in the floor slab for this purpose.
                 Once they have served their purpose they are closed by casting in concrete
                 filter.
Striking:
       Once cleaned and transported to the next point of erection, panels should be
   stacked at right place and in right order.
   Proper stacking is a clean sign of a wall – managed operation greatly aids the next
   sequence of erection as well as prevents clutters and impend other activities.
                                     CHAPTER NO: 5
                 COMPONENTS OF ALUMINIUM FORMWORK


        The basic element of the formwork is the panel, which is an extruded aluminium
rail section, welded to an aluminium sheet. This produces a lightweight panel with an
excellent stiffness to weight ratio, yielding minimal deflection under concrete loading.
Panels are manufactured in the size and shape to suit the requirements of specific
projects.
       The panels are made from high strength aluminium alloy with a 4 mm thick skin
plate and 6mm thick ribbing behind to stiffen the panels. Once they are assembled they
are subjected to a trial erection in order to eliminate any dimensional or on site problems.
            Following are the components that are regularly used in the construction.


5.1. BEAM COMPONENTS:-
            The beams like soffit corners are shaped to support floor slab panels during their
placements. Props of unique design in turn support the beams. They have maximum
length of 1500 mm to minimize deflection. The beam soffit panels are used as beam side
cover. The beam soffit bulkheads are used as beam bottoms above openings such as
doors and windows. Fig no. 3 shows the components of beam formwork
1) Beam Side Panel: - It forms the side of the beams. It is a rectangular structure and is
cut according to the size of the beam




                                  Fig No 6: Beam Side Panel
2) Prop Head for Soffit Beam: - It forms the soffit beam. It is a V-shaped head for easy
dislodging of the formwork.




                              Fig No 7: .Prop Head For Soffit


3) Beam Soffit Panel: - It supports the soffit beam. It is a plain rectangular structure of
aluminium.




                                Fig No 8: Beam Soffit-Panel

4) Beam Soffit Bulkhead: - It is the bulkhead for beam. It carries most of the bulk load.




                              Fig No 9: Beam Soffit Bulkhead

5.2. DECK COMPONENTS:-
        Deck panels support maximum deck loading with minimal deflection. They have
maximum dimension of 450 mm X 1400 mm. They are supported with beams within
deck. At perimeters of the deck areas they are supported by soffit corners and soffit
lengths. The soffit lengths are used in the straight portion of the corner joint of wall and
slab. Props support the beams. They stay in continuous contact of concrete even while the
wall and floor slab panels are being removed. Therefore under standard building practices
the AFS allows for earlier removal of formwork, reduced cycle time and a greater rate of
production. Prop head are fitted on the top of the prop and touch the concrete surface
from the bottom.



1) Deck Panel: - It forms the horizontal surface for casting of slabs. It is built for proper
safety of workers.




                                  Fig No 10: Deck Panel

2) Deck Prop: - It forms a V-shaped prop head. It supports the deck and bears the load
coming on the deck panel.




                                     Fig No 11: Deck Prop
3) Prop Length: - It is the length of the prop. It depends upon the length of the slab.




                              Fig No 12: Deck Prop Length

4) Deck Mid – Beam: - It supports the middle portion of the beam. It holds the concrete.




                               Fig No 13: Deck Mid- Beam
5) Soffit Length: - It provides support to the edge of the deck panels at their perimeter of
the room.




                                 Fig No 14: Soffit Length
6) Deck Beam Bar: - It is the deck for the beam. This component supports the deck and
beam.




                                Fig No 15: Deck Beam Bar

5.3.WALL COMPONENT:-
        Wall panels are the basic element of formwork, which consists of extruded
aluminium rail sections around the perimeter of the panel welded to an aluminium face
sheet with reinforcing ribs.This produces a lightweight panel with excellent
stiffness/weight ratio yielding minimum deflections under concrete loading.
        The panels are made of high strength aluminium alloy with a 4 mm thin skin
plate and a 6 mm thick ribbing behind to stiffen the panels. Rocker is a unique feature
attached to the bottom of wall panels. This allows the panel to be struck by pulling the
top of the panel away from the wall. This action results in panel pivoting freely at the
wall to floor slab joint. The panels are connected to each other using simple steel pins and
wedges. This allows panels to be assembled into a full housing unit using only a hammer.
The pins are made of mild steel. The wall panels are kept in a fixed distance apart by wall
ties, specially fabricated from high specification steel for various wall thicknesses.
1) Wall Panel: - It forms the face of the wall. It is an Aluminium sheet properly cut to fit
the exact size of the wall




                                   Fig No 16: Wall Panel
2) Rocker: - It is a supporting component of wall. It is L-shaped panel having allotment
holes for stub pin.




                                     Fig No 17: Rocker
3) Kicker: - It forms the wall face at the top of the panels and acts as a ledge to support




                                     Fig No 18: Kicker
4) Stub Pin: - It helps in joining two wall panels. It helps in joining two joints




                                     Fig No 19: Stub Pin
5. 4. OTHER COMPONENTS:-
1) Internal Soffit Corner: - It forms the vertical internal corner between the walls and
the beams, slabs, and the horizontal internal cornice between the walls and the beam slabs
and the beam soffit.




                               Fig No 20: Internal Soffit Corner


2) External Soffit Corner: - It forms the external corner between the components




                              Fig No 21 : External Soffit Corner




3) External Corner: - It forms the external corner of the formwork system.
The panels are connected at the vertical intersections by corner simply connects two
panels together at a right angle and has no contact with concrete face. In cast in situ
concrete, the wall to floor slab joint is the most important connection & difficult in
execution. Therefore, AFS has a special soffit corner for connecting wall and floor slab
panels. External soffit corners are used as soffit corner form the external side of the
building.




                                  Fig No 22 : External Corner
4) Internal Corner: - It connects two pieces of vertical formwork pieces at their exterior
intersections. Fig 3.18




                          FIG 3.18: - INTERNAL CORNERS19
                2. COMPONENTS OF ALUMINIUM FORMWORK SYSTEM




                      Isometric View of the Aluminium Form


          The majority of the equipment comprises of panel sections while the rest
includes vertical and horizontal corner sections, bulkheads and special floor slab beams
as shown in Fig. No. 1 that can be dismantled without disturbing the props supporting the
floor slab concrete. All panels are numbered with a code in different colours, which
determines its predetermined location. Proper coding saves time and the work can be
done speedily. Nearly 99 percent of the equipment is made of aluminium, the other one
percent is steel.20
                                   CHAPTER NO :6

              DESIGN OF FORMWORK USING SOFTWARE

        The formwork is designed using the most economical assortment of panel sizes
with the help of the state-of-the art design software. The use of the software along with
the experience and skill of the designers ensures an efficient construction process by
incorporating the optimum assembly procedures, economical panel selection and
ultimately minimizing capital and operational costs.

       The formwork requirement depends upon various parameters such as desired
speed of construction, economy required. After considering all of these, various options
are offered at the estimate stage to the client. The system is flexible in design and can
form any architectural or structural configuration, such as stairs, bay windows, curved
features etc. Designers consult the architects and structural designers during design stage
in order to avoid costly modifications of RC members during construction stage.
It is thus essential to select the most practical and economic blend of standard formwork
components required for the building at the preconstruction design phase itself.
       Using Bespoke design software, the formwork is designed using the most
economical assortment of panel sizes. The combination of bespoke software and the
experience of MIVAN designer‟s guarantees...


a) Most efficient construction process incorporating the optimum assembly procedures.
b) Economical panel section.
c) Ultimately minimizing capital and operational cost.
6.1.Bespoke software:

It is also known as Custom software is a type of software that is developed either for a
specific organization or function that differs from or is opposite of other already available
software (also called off-the-shelf or COTS software). It is generally not targeted to the
mass market, but usually created for companies, business entities, and organizations.
Custom software is also when companies or governments pay for customized software
for budget or project managing.

Examples of bespoke software include commercial products such as commercial
websites, business databases and software for governments. Non-commercial custom
software development is common in academic and open source circles.

Complex custom software can be developed on an increasingly small scale through the
rise of rapid application development frameworks. This means that smaller companies,
charities or even individuals are able to benefit from complex software based on pre-built
building blocks which are then customized to suit.

Advantages of Bespoke Software:-

      It has been specifically designed for your particular requirements and can be
       tailored to fit in exactly with the way that your business or organisation wishes to
       operate.
      It can be customised to interface with other software that you operate with the
       potential to provide you with a fully integrated IT infrastructure across your
       whole organisation.
      You have a direct relationship with the developer, so it's easier to influence future
       development or get specific changes made.
      Users will usually find it easier and more intuitive to use as it should not contain
       unnecessary or superfluous facilities and should operate in the way that they are
       used to working.
      It can incorporate business processes that are specific to you and which do not
       exist in any packaged solution.
      The use of professionally developed bespoke software could give you a
       significant advantage over your competition.

Drawbacks of Bespoke Software :-

      Finding a competent developer.
      Higher costs and longer lead times.



Conclusions:-
Having a bespoke application developed for you can potentially provide you with major
business and commercial benefits and allow you to gain significant competitive
advantage. However you have to expect to pay more for it than for a packaged solution
and it is also essential that you use a professional developer who works to Best Practice
standards and who is happy to provide you with the source code to your application.

6.2. Software:-
PASCHAL software provides the necessary support for optimised formwork design and
application. The software generates formwork plans and relevant material lists.


PASCHAL-Plan light - Automated Formwork Planning:-


        The construction layout is entered into PASCHAL-Plan light (PPL), or loaded in
DXF file format. The application then generates a formwork setup for the required
layout. By setting up default values, the user can modify the formworks setup according
to individual requirements, and has the option to select from formwork systems
“Logo.3”, “Modular”, or “Athlet”.

The material lists generated by PPL also contain geometric data such as formwork
surface area, volume of concrete and formwork time requirements. The program
automatically computes the best possible formwork setup for the project. You can
generate a side view for each of the wall sides, showing all elements and setup parts.




         PPL is available in the versions PPL-START and PPL-PLUS. The PLUS version
provides the additional feature to manually edit automatically generated formwork
solutions, and to identify stock shortages, or generate entire sales & leasing offers.



PASCHAL-Plan pro - Formwork Planning with AutoCAD:-

        PASCHAL-Plan pro (PPP) can handle the most demanding formwork projects.
The application provides predefined elements, for which data has been prepopulated.
That means that formwork elements can only be placed at correct positions, and relevant
accessories can only be used at their predefined locations on the element. The software
provides 2D and 3D views.
PASCHAL Ident:-
         PASCHAL Ident technology assigns a unique electronic number to each of the
formwork elements - similar to a human fingerprint. The process guarantees unique and
unmistakable identification, and is prerequisite for leasing or any other credit processes.

Users are able to identify each element and use them in planning. For the first time
PASCHAL Ident makes this technology available for formwork projects. It is system
integrated, and therefore completely resistant against accidental damage on the
construction site, making it far superior to other systems, like barcodes, colour or other
types of tagging. Based on this unique identification process, it has now for the first time
become possible to finance formworks through leasing. It has never been easier to build
and manage a sophisticated formwork park.
                               CHAPTER NO: 7

 ADVANTAGES OF ALUMINIUM FORMWORK OVER
  CONVECTIONAL FORMWORK AND COMPARISON



1)More seismic resistance: - The box type construction provides more seismic
resistance to the structure.

2)Increased durability: - The durability of a complete concrete structure is more
than conventional brick bat masonry.

3) Lesser number of joints thereby reducing the leakages and enhancing the
durability.

4)Higher carpet area- Due to shear walls the walls are thin thus increasing area.

5)Integral and smooth finishing of wall and slab- Smooth finish of aluminium can
be seen vividly on walls.

6)Uniform quality of construction – Uniform grade of concrete is used.

7)Negligible maintenance – Strong built up of concrete needs no maintenance.

8)Faster completion – Unsurpassed construction speed can be achieved due to
light   weight of forms

9)Lesser manual labour- Less labour is required for carrying formworks.

10)Simplified foundation design due to consistent load distribution.

11)The natural density of concrete wall result in better sound transmission
coefficient.
                                          Table 8.1
         RELATIVE COMPARISON OF IN – SITU “ALUMINIUM FORM” SYSTEM
                                              WITH
                             CONVENTIONAL CONSTRUCTION


Sr FACTOR        CONVENTIONAL               IN – SITU ALUMINIUM                  REMARKS
 .                                              FORM SYSTEM
No
                                          Superior.                         Superior quality
                                          In – Situ casting of whole        in “System
                                          structure and transverse walls    housing”
                                          done in a continuous operation,
                                          using     controlled   concrete
                                          mixers obtained from central
1    Quality            Normal
                                          batching, mixing plants and
                                          mechanically placed through
                                          concrete buckets using crane
                                          and compacted in leak proof
                                          moulds using high frequency
                                          vibrators
                The        pace      of   In this system, the walls and     System
                construction is slow      floors are cast together in one   construction
                due to step – by –        continuous operation in matter
                step completion of        of few hours and in built         is
                different stages of       accelerated curing overnight
                activity the masonry      enable removal and re-use of      much faster.
                is required to be laid    forms on daily cycle basis.
    Speed of brick         by    brick.
2   constructio Erection             of
    n.          formwork, concreting
                and        deshuttering
                forms is a two – week
                cycle. The plastering
                and other finishing
                activities          can
                commence           only
                thereafter.
                In the case of RCC        The Room – Sized wall panels
                structural framework      and the ceiling elements cast
3   Aesthetics. of column and beams       against steel plates have
                with partition brick      smooth finishing and the
                walls is used for         interiors have neat and clean
                  construction,      the   lines     without     unsightly
                  columns and beams        projections in various corners.
                  show         unsightly   The walls and ceilings also
                  projections in room      have smooth even surfaces,
                  interiors.               which only need colour/white
                                           wash
                  Cement        plastered  Textured / pattern coloured       Permanent facia
                  brickwork,      painted  concrete facia can be provided.   finishes feasible
    External      with cement – based      This will need no frequent        with minor extra
4
    finishes.     paint. Finishing needs   repainting.                       initial cost
                  painting every in
                  three years.
    Useful        Efficiency around       Efficiency around 87.5%            More efficient
    carpet area   83.5%                                                      utilization of land
5   as % of                                                                  for useful living
    plinth                                                                   space.
    area.
    Consumpti
    on of basic
    raw
    materials




                  Normal                   Consumption somewhat more Although greater
    Cement.                                than that used in conventional consumption
                                           structures.                    strength      and
                                                                          durability is also
                                                                          more

6




                                                                             Steel requirement
                                                                             is more, as it is
                                                                             required for the
                                                                             shear         wall
                                        It may, however will be              construction. But
                                        slightly     more       than         shear         wall
                  Reinforcing     steel corresponding load – bearing         construction
    Reinforcin    required is less as brick wall construction for            increases safety
    g Steel       compared to the in which, requirements of IS 456           against
                    situ construction as have to be followed for system earthquake.
                    RCC framework uses housing.
                    brick      wall   as
                    alternative



      Maintenan     In maintenance cost, The walls and ceiling being          It      can      be
      ce            the major expenditure smooth and high quality             concluded      that
                    is involved due to :    concrete repairs for plastering   maintenance cost
                                            and leakage‟s are not at all      is negligible.
                           Repairs    and required frequently.
                       maintenance       of
                       plaster of walls /
7                      ceiling etc.

                     Painting of outer
                      and inner walls.

                    Leakages due to
                    plumbing      and
                    sanitation
                    installation.


    1.3 Aluminium Formwork System in India :
          In 1998, M/s. B. E. Billimoria & Co. Ltd., of Mumbai imported Aluminium
       formwork to construct residential housing complex for the Nagari Nivara Parishad
       housing project in Malad (E), Mumbai. This was the first project in India. The second
       project was done by M/s. Khurana Engineering of Ahmadabad to construct 1400
       EWS units for the Ahmadabad Urban Development Authority. The third project was
       done by M/s. Naiknavare & Associates in Pune to construct 660 two BHK apartments
       in fifteen, 11 storey buildings.
              After experiencing the benefits of the system, M/s. Naiknavare & Associates
     decided to develop a similar formwork system in India, instead of importing the
     formwork. After one year of research and development M/s. Naiknavare & Associates
     were successful in designing and manufacturing an improved Aluminium formwork
     system namely ALUFORM.
                                       Table 3.8.2: -

   Effect of construction speed on the cost of flat. (Courtesy: Jogeswari
                       Vikhroli link road, NNP Nivara Parishad,MMRDA)


Description                                   Construction Speed
                            A                B                C                 D
Construction speed    3 flats/day     4 flats/day     5 flats/day       6 flats/day
Period of const.      23 months       18.7 months 16.2 months           14.2 months
Forming area          741.9           989.2           1236.5            1483.8
Misc formwork         55.5            55.5            55.5              55.5
Total formwork to     797.4           1044.7          1292              1539
be ordered
Cost of formwork      14353200        18804600          23256000        27707400
Two third of the      9568800         12536400          1550400         18471600
loaded cost
Profit & Overhead     1435320         1880460           2325600         2770740
15%
Total Rs.             11004120        14416860          17829600        21242340
Cost per flat, Rs     9825            12872             15919           18966


According to the study carried out ,it is clesrly seen from the above table:

       It is seen that in column A construction speed is 3Flats/day and it requires less
total formwork to be ordered as compared to that in column D which has construction
speed of 6Flats/day. Hence the cost of formwork is less in former case.As the
construction speed increases the final cost of flat increases.
                                     CHAPTER NO:8

                                     LIMITATIONS
            Even though there are so many advantages of MIVAN formwork the
limitations cannot be ignored. However the limitations do not pose any serious problems.
They are as follows: -

1) Because of small sizes finishing lines are seen on the concrete surfaces.
2) Concealed services become difficult due to small thickness of components.
3) It requires uniform planning as well as uniform elevations to be cost effective.
4) Modifications are not possible as all members are caste in RCC.
5) Large volume of work is necessary to be cost effective i.e. at least 200 repetitions of
the forms should be possible at work.
6) The formwork requires number of spacer, wall ties etc. which are placed @ 2 feet
c/c; these create problems such as seepage, leakages during monsoon.
7) Due to box-type construction shrinkage cracks are likely to appear.
8) Heat of Hydration is high due to shear walls.
9)    Superior quality paint is required.


     Remedial Measures:-


            In external walls, ties used in shutter connection create holes in wall after
     deshuttering. These may become a source of leakage if care is not taken to grout the
     holes. Due to box-type construction shrinkage cracks are likely to appear around door
     and window openings in the walls. It is possible to minimize these cracks by
     providing control strips in the structure which could be concreted after a delay of
     about 3 to 7 days after major concreting. The problem of cracking can be avoided by
     minimizing the heat of hydration by using flyash.
                                    CASE STUDY
            The City and Industrial Development Corporation and Organization (CIDCO)
of Maharashtra are responsible for the development of Navi – Mumbai. It has undertaken
massive projects to achieve this goal and has encouraged use of latest technologies to
complete these projects. In recent years it has undertaken large – scale constructions of
houses in Navi – Mumbai.



 COMPLETED PROJECT WITH ALUMINIUM FORMWORK


SPAGHETTI at KHARGHAR

Location:                Navi – Mumbai.
Country:                 India.
Client:                  CIDCO and L&T ECC
Scope:                   4 No. Blocks on each floor of 4, 5, 6, and 7 Storey Apts.
Design:                  Load Bearing wall & slab.
Cycle:                   4 days per floor.
System formwork:         6000 sq.mt.
Contract Start Date:     November 2003.
Project Type (s):        High rise, residential building having 16 buildings in all.
Architect:               Hafeez Contractor



The building in plan made an angle of 1720, 168º and 1610 with each other. The quality
of construction is maintained at the site with the use of RMC. The RMC plant has a
capacity of producing 90 cubic meter of concrete of concrete per hour. The concrete used
was of 25 grades. The construction from foundation up to stilt is done with conventional
practice while the upper floors are constructed using „MIVAN‟ technology. The
construction company has imported three sets of aluminium forms. The cost is about
Rs.500/- sq.ft as against Rs.650/- sq.ft using conventional methods. Thus it can be said
that even though the cost of construction is little bit high it has an unmatched quality
compared to the conventional method.
       MIVAN formwork played a vital role in the construction of the project. The
project was completed not only on stipulated period of time but also paid off with its
attributes. Speedy & quality dwelling units were provided to the people of low income
groups at very reasonable costs. MIVAN is a definitely future of this ever growing
construction industry with lots of project still awaiting its touch of excellence.
                                     CONCLUSION :

           The advantages of the Aluform System are obvious. Apart from speed due to
simplicity of the formwork, it eliminates the need for beam formwork and corresponding
centering. Number of cold joints in concrete work is reduced substantially. The joints
between brick masonry walls and beams & columns are eliminated which coupled with
the strong and dense controlled concrete used to satisfy the durability criteria as called for
by the specifications make these structures virtually maintenance-free for several years.
The walls and the slabs form a rigid, monolithic, and strong structure. It is also worth
noting that the dimensions and right angles at meeting points of wall-to-wall, wall to
floor, wall to ceiling etc. are very accurate.
            The Aluminium Formwork System can achieve not only faster rate of
construction but can also bring down the structural cost by 20 to 25 % over the
conventional method with lesser labour inputs. This system is ideally suited for Indian
conditions; where total dependence on heavy plants and machinery as in case of precast
factories can be avoided without sacrificing the speed of construction.Hence Aluform
System is an excellent solution to the problems in the present housing situation because
of its specific merits.
              We thus infer ALUMINIUM            form construction is able to provide high
quality construction at unbelievable speed and at reasonable cost. This technology has
great potential for application in India to provide affordable housing to its rising
population.
              Thus it can be concluded that quality and speed must be given due
consideration with regards to economy. Good quality construction will never deter to
projects speed nor will it be uneconomical. In fact time consuming repairs and
modification due to poor quality work generally delay the job and cause additional
financial impact on the project. Some experts feel that housing alternatives with low
maintenance requirements may be preferred even if at the slightly may preferred even if
at the higher initial cost.
                                  REFRENCES



   1. Carol., A., “(2001)”. Editor. “Times Journal Construction and Design”. Oct-Dec
      2001, pp Editorial.
   2. “Census of India”., “(2001)” “Table 500-012”. pp-48.
   3. Jain and Jain., “(1993)”. “Design of Formwork”. “Design of Concrete
      Structures.”, Edition 1993, pp 595-606.
   4. Jana., V., G., & Kagale., Y., P., “(2005)”. “Indegnisation of Mass housing
      technology”. “Indian Concrete Journal”, July2005, Volume 79, pp. 41-46.
   5. Kulkarni., D., V., “(2001)”. “ First Rate Forms”. “Times Journal Construction and
      Design”. Oct-Dec 2001, pp 22-23.
   6. “National Building Organization”., “(2001)”. pp-25

WEB SITE CONSULTED
AskACC- ( Definition of Formwork)
                   URL (www.askacc.com)
   2. Answers- (Classification of formwork)
                   URL (www.answers.com)
   3. Army Website- ( Prefabricated buildings)
                   URL (www.army.com)
   4. Encyclopedia- (Definition of Formwork)
                   URL (www.wikipedia.com)
   5. OUTINARD- (Components, Assembly)
                   URL (www.outinard.com)
   6. MIVAN- (Components, Assembly, Case studies)
                   URL (www.mivan.com)
                                  3. ADVANTAGES
1. Less use of skilled labour and heavy machinery
2. Speed of construction
3. High precise quality of work
4. Repetition of formwork
5. Flexibility of System
6. Simplicity
7. Cost Efficiency
8. Superior Earthquake Resistance
                                   4. LIMITATIONS

1. Architectural changes are not possible in the     structure ( but some walls can be of
  brickwork or openings can be entertained ).
2. Due to the tremendous speed of construction, working capital finance needs to be
  planned in advance.
3. Superior quality paint is required.
                                     5.CONCLUSION
The advantages of the Aluform System are obvious. Apart from speed due to simplicity
of the formwork, it eliminates the need for beam formwork and corresponding centering.
Number of cold joints in concrete work is reduced substantially. The joints between brick
masonry walls and beams & columns are eliminated which coupled with the strong and
dense controlled concrete used to satisfy the durability criteria as called for by the
specifications make these structures virtually maintenance-free for several years. The
walls and the slabs form a rigid, monolithic, and strong structure. It is also worth noting
that the dimensions and right angles at meeting points of wall-to-wall, wall to floor, wall
to ceiling etc. are very accurate.
                  The Aluminium Formwork System can achieve not only faster rate of
construction but can also bring down the structural cost by 20 to 25 % over the
conventional method with lesser labour inputs. This system is ideally suited for Indian
conditions; where total dependence on heavy plants and machinery as in case of precast
factories can be avoided without sacrificing the speed of construction.Hence Aluform
System is an excellent solution to the problems in the present housing situation because
of its specific merits.

				
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