Mivan-A Versatile Formwork
A SEMINAR ON
SUBMITED BY Tilak Bhattacharya (B. E. Civil)
UNDER GUIDANCE OF Mr. A. T. Jadhav
RAJARAMBAPU INSTITUTE OF TECHNOLOGY RAJARAMNAGAR, (Sakharale) Dist: Sangli Pin: 415414 2006-2007
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Kasegaon Education Society’s Rajarambapu Institute of Technology, Rajaramnagar. Department of Civil Engineering
This is to certify that the following student of B.E. Civil Engineering has successfully completed the seminar report entitled
In the partial fulfillment of Bachelor’s Degree in Civil Engineering, of “Shivaji University, Kolhapur” during academic year 2006-2007. Name:
Roll No:
TilakBhattacharya
4101
Guide
Mr. A. T. Jadhav
H.O.D.
Principal
Prof. P. S. Patil
Dr.Mrs. S. S. Kulkarni
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INDEX OF CONTENTS A.
ABSTRACT
i
I.
Introduction ………………………………………1
I.1 A Brief Introduction to the Construction Industry…………………….……...3 I.2 Housing Scenario in India………………………………………………….…5 I.3 Innovations in Construction………………..…………………...………….…8
II.
Formwork
II.1Formwork and Formwork Requirements……………………………………11 II.2Classification of Formwork……………………………………………..…...12 2.3 Loads acting on Formwork.….........................................................................16 2.4 Strength of Formwork (General Design)…………………………………….17 2.5 Aluminum Formwork……………………………………....………………..18
III. MIVAN – A Versatile Formwork III.1 Background…………………………………………………………………..23 III.2 Components of MIVAN Formwork………………………………….………25 III.3 Formwork Assembly…………………………………………………………35 III.4 Construction through MIVAN Formwork…….……………………………..41 III.5 Bespoke Software……………………………………………………………45 III.6 Site Management – One day Cycle……………………………………….….46 III.7 Speed of Construction – Four Day Cycle……………………………………47 III.8 Design Aspects of MIVAN Formwork………………………………………48 III.9 Economics……………………………………………………………… ……49 3.10 Quality………………………………………………………………………..50
IV. Advantages and Limitations. IV.1 IV.2 IV.3
Advantages………………...…………………………………………………51 Limitations…………...………………………………………………………52 Remedies……………………………………………………………………..53
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V. V.1
Case Study – Spaghetti Mass Housing Society.....54 Discussion……………………………………..………………………….55
VI. Conclusion………………...……………………..56 VII. References…………………………………………i VIII.List of figures………………………...........………ii IX. List of tables……………………………………...iii
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1.0 Introduction Besides, food and clothing, shelter is a basic human need. India has been successful in meeting the food and clothing requirements of its vast population; however the problem of providing shelter of all is defying solutions. “While there has been an impressive growth in the total housing stock from 65 million in 1947 to 187.05 million in 2001, a large gap still exits between the demand and supply of housing units. The Working Group on Housing for the 9th five-year plan estimated the housing shortage in 2001 at 19.4 million units- 12.76 million in rural area and 6.64 million in urban area. The shortage of housing is acutely felt in urban areas –more so in the 35 Indian cities, which according to the 2001 census have a population of more than a million”. ….. (Carol., 2005). In metro cities, particularly in Mumbai, Delhi and Kolkata- each having a population in excess of 10 million- the problem is still aggravated. A host of factors are responsible such as the phenomenal growth in population- mainly due to relentless rise in migration- non availability of land, legal hurdles in the form of Land Ceiling and Rent Control (LCRC) acts, paucity of funds, absence of cost effective construction techniquesto mention only a few. Barring a few exceptions, no serious attempts were made in the past to find meaningful solutions to these problems. As a result, we are witnessing a large scale proliferation of slums and squatter settlements in the metros. The National Housing and Habitat Policy, announced in July 1998, laid stress on the creation of an enabling environment, wherein government assumed the role of a facilitator and the private sector was expected to play a vital role in providing large-scale housing. In the recent years, a number of fiscal measures initiated by the government have given a boost to the housing sector. The easy availability of finance, coupled with lower interest rates and a variety of tax incentives announced by the government in the successive union budgets have triggered massive housing construction in urban and semi urban areas, especially in the middle and higher income groups. However, the low income groups seem to have been left out of the current housing boom.
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IN A DEMOCRATIC SET-UP of INDIA, one would agree that this section of the population cannot be ignored and that they also need to be provided with affordable housing; but how this can be achieved remains a permanent question. In this context, the recent affords made in Mumbai under the aegis of the Metropolitan Urban Transport Project (MUTP), Metropolitan Urban Infrastructure Project (MUIP), and the Slum Rehabilitation Authority (SRA) of the government of Maharashtra can provide some guidance. “It is reported that under MUTP and the MUIP schemes nearly 50,000 tenements are being constructed presently and about 20,000 families have already shifted to new flats”. Editor (ICJ). This paper deals with all the aspects of MIVAN technology, an aluminium formwork developed by the company MIVAN itself. The salient features of this formwork are its speed of construction, quality of construction, seismic resistivity and its economy. All these features are elaborately described in this paper.
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1.1 A Brief Introduction to the Construction Industry Construction is one of the significant sectors of Indian economy and is an integral part of the development. Today India’s urban population is the second largest in the world and its future development leads to increased demand for housing To cope with this problem India should desperately need to plan for acquisition of land and rapid creation of dwelling units. Construction is a complex process involving basically the areas of Architectural planning, Engineering & Construction. Despite of the boom in construction activities in urban centers in recent years across the country, the scenario on the housing front remains far from satisfactory. “Latest statistics indicate that the total housing shortage in the urban sector was 7.75 million in 1997. An additional demand of 9.7 million units is expected to be generated in this sector during the period 2002–2007. According to the Federation of Indian Chamber of Commerce and Industries (FICCI), keeping in view the existing housing crisis, the country shall need addition of more 2.5 million new dwelling units annually”.…..( Kulkarni, 2001). The recent years voiced the active participation private sectors in finding the solution over the prevailing situation on housing front. Keeping in view the gigantic task of providing affordable shelter to masses, adoption of a cost – effective technology assumes greater significance. The present strain on Indian economy and the overgrowing demands for housing calls for adoptions of appropriate building technology which could lead to economy and speed in construction. As a result of experimentation of innovate construction techniques and modern construction management it is now possible to achieve an overall saving to the extent of 10% in the total cost of housing construction compared to the cost of traditional housing. There is growing realization today that speed of construction needs to be given greater importance especially for large housing projects. This is not only essential for the faster turnover of equipment and investment – leading possible to the reduction in the housing cost – but also for achieving the national objective of creating a large stock to
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overcome shortest possible time. Fortunately some of the advanced technologies catering to faster speed of construction are already available in the country. For e.g. prefabrication, autoclaved blocks, tunnel formwork, aluminum formwork (MIVAN Technology) of construction etc.
1.2 Housing scenario in India The progress made by the construction industry of any country could be considered as the index of development of that country. Further, the number of pucca houses built in any country could be another index. While there has been a progressive rise in stock of housing in India since independence, the speed thereof has not kept pace with the rapid growth of population and urbanization. As a result, the shortage of accommodation is increasing continuously and the situation has become acute in urban areas.
Table 1.1:- Total population and percentage of population in unauthorized construction.* (Source: Table 500-012 of census India 2001) Year
Population Million
Population in authorized Population in unauthorized
1961 4.15 1971 5.97
accommodation, million % 0.50 1.60
accommodation, million % 12 27
1981 8.23 1991 9.93
3.25 4.45
40 45
2003 12.50
6.25(approx)
50
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Table 1.2:- Shortage of housing in India (all figures in million) ** ** Source: As per estimates of National Building Organization
From the above tables and graphs the following pictures emerges:i) While the total number of households (housing shelter) have increased by about 30 Percent, between 1961to 2003, the total shortage continues to be the same at about 20% of the total households. ii) The increase in shortage of housing in urban areas has been 50 percent as against 25 percent in rural areas. “The severity of the problem is critical especially in the metropolitan area and a classic example is Mumbai, the housing shortage is as high as 50 percent as
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against national average of 20 percent”…. (Telang.,2005). “The problem of housing the millions is gigantic and complex and it needs a totally innovative governmental, social and technical approach for arriving at workable solutions, consistent with limitations of a democratic setup”. ….. (Bongiwar.,2005)
1.3 INNOVATIONS IN CONSTRUCTION The traditional mode of construction for individual houses comprising load bearing walls with an appropriate roof above or reinforced concrete (RC) framed structure construction with infill masonry walls would be totally inadequate for mass housing construction industry in view of the rapid rate of construction. Further, such constructions are prone to poor quality control even in case of contractors with substantial resources and experience. “For undertaking mass housing works, it is necessary to have innovative technologies which are capable of fast rate construction and are able to deliver good quality and durable structure in cost effective manner”.…..( Shrikande., et.al,2005) Several systems are adopted at different places in the world; eventually the systems which are reasonably economical and easy for operation with skilled labor are useful in India. Certain systems are in vogue and more and more contractors are trying to bring in new technologies. These are essentially based on the basis of mode of construction, namely, pre-cast construction or in-situ construction. 1.3.1:- Cast-in-Situ Construction Pre-cast and cast-in-situ are techniques that are used for quick construction. Precast includes the wall-panel units and slab units directly added to building structure. The use of aluminium also evolved as one of the technique for quick construction by use of aluminium and steel (tunnel) formwork. As a matter of fact the cost of the formwork may be up to 25% of cost of the structure in building work, and even higher in bridges, it is thus essential that the forms are properly designed to effect economy without sacrificing strength and efficiency. Certain patented systems based on imported technologies such as “Mascon System” (Canada), “Mivan System” (Malaysia) have come on the Indian scene in recent
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years. In these systems traditional column and beam construction is eliminated and instead walls and slabs are cast in one operation at site by use of specially designed, easy to handle (with minimum labor and without use of any equipment) light weight pre-engineered aluminium forms. Rapid construction of multiple units of a repetitive type can be achieved with a sort of assembly line production by deployment of a few semiskilled labors. The entire operation essentially comprises fitting and erecting the portion of shuttering as already determined (the optimization in use is determined by appropriate planning) and then carrying out concreting of the walls and slabs. Props are so designed that they stay in position while de-shuttering of slabs and/or takes place. The dimensional accuracy of the formwork is of high order. Therefore any possibility of errors does not rise.
1.3.2 “3-S” SYSTEM OF PRECAST CONSTRUCTION An engineered system of building construction, namely “3-S” system was developed by B.G.SHIRKE CONSTRUCTION TECH LTD., for achieving, speed, strength, safety and economy in construction practices. The system involves structural elements such as pre-cast hollow column shells pre-cast concrete beams, light weighed reinforced cellular autoclaved concrete slabs for floor and roofs constituting the basic structural formwork. The “3-S” system involves activities for construction of building such as: I. Cast in-situ sub-structure including foundations, stem columns, plinth beams, plinth masonry. II. Erection of partial pre-cast components, jointing of these components using cast in-situ concrete with appropriate reinforcement. III. Lying of reinforced cast in-situ screed over slab panels, construction of panels, construction of walling, flooring, plastering, water proofing etc.
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Achieving the “3-S” system in the MIVAN formwork is quite easy. MIVAN formwork has got the unsurpassed speed of construction due to saving time for required time in masonry and plastering. The strength of raw aluminium is very less but when alloyed with other materials prove to be strong enough to use as a formwork . To ensure safety in the site, an integrated safety/ working platform is developed which ensures labor safety during erection and striking of the formwork. Economy is also one of the main factors of any system. The MIVAN formwork proves to cost efficient as it can be used efficiently for 250 times. 1.3.3 Present Technologies Available in INDIA Some of the advanced technologies of formwork catering to the speed of construction are given below: To name a few:1) The Prefabrication Technology: - The Pre-cast concrete elements in roofs, floors and in walls have become more common as these eliminate shuttering; centering & plastering labor and saves material cost.
Fig 1.1: - Prefabricated Technology (Raymond, 2001) 2) Tunnel Formwork Technology: - It is a technology constructing large no of housing within short time using steel forms to construct walls & slabs in one continuous pour. 12
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Fig 1.2:- Tunnel formwork (Raymond, 2001) 3) Outinard Technology :- Outinard’s superior engineering, the use of high quality steel and High Performance quality control result in a vastly superior Wall Form system.
Fig 1.3: -Outinard Technology (Raymond, 2001) 4) Mascon Technology:-The Mascon Construction System is a system for forming the cast in-place concrete structure of a building. It is also a system for scheduling and controlling the work of other construction trades such as; steel reinforcement, concrete placement, and mechanical and electrical trades.
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Fig 1.4: - Mascon Technology. (Raymond, 2001)
Chapter 2 2. FORMWORK When concrete is placed, it is in plastic state. It requires to be supported by temporary supports and castings of desired shape till it becomes sufficiently strong to support its own weight. This temporary casing is known as the formwork or forms or shuttering. The term moulds is sometimes used to indicate formwork of relatively small units such as lintels, cornices etc. 2.1.1 Definition of formwork:“Forms or moulds or shutters are the receptacles in which concrete is placed, so that it will have desired shape or outline when hardened. Once concrete develops the adequate strength to support its own weight they can be taken out”. .. (ACC). “Formwork is the term given to either temporary or permanent moulds into which concrete or similar materials are poured”. … (Wikipedia Encyclopedia).
2.1.2 Requirements of a good formwork The essential requirements of formwork or shuttering are: a) It should be strong enough to take the dead and live loads during construction.
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b) The joints in the formwork should be rigid so that the bulging, twisting, or sagging due to dead and live load is as small as possible. Excessive deformation may disfigure the surface of concrete. c) The construction lines in the formwork should be true and the surface plane so that the cost finishing the surface of concrete on removing the shuttering is the least. d) The formwork should be easily removable without damage to itself so that it could be used repeatedly.
2.2 Classification of Formwork Formwork can be classified according to a variety of categories, relating to the differences in sizes, the location of use, construction materials, nature of operation, or simply by the brand name of the products. However, the huge amount of tropical wood being consumed each year for formwork has resulted in criticism from environmentalists, as well as the continual escalation of timber prices. As a result, there has been a strong tendency to use other formwork materials or systems to replace timber. The different categories in which formwork can be classified are: a)
According to size.
b)
According to location of use.
c)
According to materials of construction.
d)
According to nature of operation.
e)
According to brand name of the product.
2.2.1 Classification according to size Classification according to the size of formwork can be very straightforward. In practice, there are only two sizes for formwork; small-sized and large-sized. Any size which is designed for operation by workers manually is small-sized. Very often, the erection process is preferably handled by a single worker, with site work best done independently to avoid possible waiting times. Due to reasons of size and weight, the materials and construction of small-sized formwork are thus limited. At present, the most 15
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common systems are made of timber and aluminium, and are usually in the form of small panels. There is seldom medium-sized formwork. In cases in which large-sized formwork is used, the size of the form can be designed as large as practicable to reduce the amount of jointing and to minimize the amount of lift. The stiffness required by large-sized formwork can be dealt with by the introduction of more stiffening components such as studs and soldiers. The increase in the weight of the formwork panels is insignificant as a crane will be used in most cases.
2.2.2
Classification according to the location of use: -
There are not many effective formwork systems for stairs and staircases. The complicated three-dimensional nature of an element involving suspended panels and riser boards, as well as the need to cope with very different spatial and dimensional variances as required by individual design situations, cannot be achieved by a universally adaptable formwork system (fig 2.1).
Fig 2.1 - Staircase under traditional formwork arrangement using timber (Raymond. 2001) Classification according to materials of construction Materials used for formwork are traditionally quite limited due to finding the difficult balance between cost and performance. Timber in general is still the most popular formwork material for its relative low initial cost and adaptability Steel, in the form of either hot-rolled or cold-formed sections and in combination with other sheeting
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materials, is another popular choice for formwork materials.In the past two to three years, full aluminium formwork systems have been used in some cases but the performance is still being questioned by many users, especially in concern to cost and labor control (fig 2.2 & 2.3).
Fig 2.2 - Typical steel form system to construct a core
Fig 2.3 - Aluminium formwork for wall, floor
wall.
and other architectural features (source Raymond,2001).
2.3
Classification according to nature of operation Formwork can be operated manually or by other power-lifted methods. Some
systems are equipped with a certain degree of mobility to ease the erection and striking processes, or to allow horizontal moment using rollers, rails or tracks. Timber and aluminium forms are the only manually-operable types of formwork. They are designed and constructed in ways that they can be completely handled independently without the aid of any lifting appliances. On the other end of the scale, such systems are used in very large-sized and horizontally-spread buildings with complicated layout designs which require the systems' flexibility. Fig 2.4 & 2.5 shows the formwork system allowing the incorporation of pre-cast elements and self climbing form with hydraulic jack devices respectively.
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Photo 2.4 - formwork system allowing the Photo 2.5 - example of a self-climbing form with Incorporation of pre-cast elements (govt. quarters) (source Raymond, 2001)
detail of the hydraulic jack devices
2.5 Classification according to brand name of the product Several patented or branded formwork systems have successfully entered the local construction market in the past decade. These include products from brands SGB, RMD, VSL, MIVAN, Thyssen and Cantilever. Each of these firms offers its own specialised products, while some can even provide a very wide range of services including design support or tender estimating advice. As the use of innovative building methods is gaining more attention from various sectors in the community, advanced formwork systems are obviously a promising solution. The input through research and development by the wellestablished formwork manufacturers is of no doubt contributing to efforts in these areas. (fig 2.6)
Fig 2.6:-VSL FORMWORK (Source Raymond, 2001) 2.3 Loads acting on Formwork
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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. For 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. Aluminium 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.
2.4 Design Aspects
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In MIVAN formwork we give stress on shear wall rather than conventional framed structure of columns and beams. In general the design of a wall formwork is described as under. Consider designing a wall for 30 cm thick and 5 m high. The concrete is poured at shifts of 1.5 m each. The sheathing is placed horizontally and spans between vertical studs are under horizontal pressure due to wet concrete. These Studs are backed by the horizontal pieces called Wales which are tied by bolts, passing through the wall. Thus pressure on either side of the wall is self balanced as shown fig 2.4.1. The pressure exerted by concrete will be 2300 equivalent weight of fluid at a depth of h meters. Taking lowest portion of the sheathing, the pressure is equal to 2300 x 1.5 =3450 kg/ sq.m. If the sheathing is 25 cm thick, the spacing x of the studs is given by M=bd²/6 x σ; σ = 102 kg/ sq cm where σ is safe fiber-stress. Or, Or,
3450 x x² = 1 x 2.5²/6 x 102 100² x 10 x = 55.5 cm.
Adopt the spacing of 55 cm apart. If the spacing of wales is 68cm, the average pressure on the studs between two bolts will be 2300(1.5-68/2) x .55 =1468 kg per meter run, assuming concrete pouring is started at level of a low bolts. Max S.F. at edges of clear span = 1468 x 0.6/2 = 440 kg. Assume studs to be 7.5 cm x 10 cm, Shear stress = 3/2 x 440/(7.5 x 10) = 8.8 kg/ sq cm. Maximum fiber stress = 6785 x 10/2 = 54.3 kg/ sq cm. 7.5 x 10³/12 So the section adopted is satisfactory. 2.5:- Aluminium Formwork
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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. 2.5.1 MERITS OF ALUMINIUM FORMWORK: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.
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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. 2.5.2: -Comparison of Aluminum Form Construction Technique Over Conventional Forms: Advantages of aluminium formwork over conventional construction
i.
More seismic resistance: - The box type construction provides more seismic resistance to the structure.
ii.
Increased durability: - The durability of a complete concrete structure is more than conventional brick bat masonry.
iii.
Lesser number of joints thereby reducing the leakages and enhancing the durability.
iv.
Higher carpet area- Due to shear walls the walls are thin thus increasing area.
v.
Integral and smooth finishing of wall and slab- Smooth finish of aluminium can be seen vividly on walls.
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vi.
Uniform quality of construction – Uniform grade of concrete is used.
vii.
Negligible maintenance – Strong built up of concrete needs no maintenance.
viii.
Faster completion – Unsurpassed construction speed can be achieved due to light weight of forms
ix.
Lesser manual labour- Less labour is required for carrying formworks.
x.
Simplified foundation design due to consistent load distribution.
xi.
The natural density of concrete wall result in better sound transmission coefficient.
Table 2.1:- RELATIVE COMPARISON OF IN – SITU “ALUMINIUM FORM” SYSTEM WITH CONVENTIONAL CONSTRUCTION.
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Sr. No
1
2
FACTOR
Quality
CONVENTIONAL
IN – SITU ALUMINIUM FORM SYSTEM
Normal
The pace of construction is slow due to step – by – step completion of different stages of activity the masonry is required to be laid brick by brick. Speed of Erection of formwork, construction. concreting and deshuttering forms is a two – week cycle. The plastering and other finishing activities can commence only thereafter.
Aesthetics.
In the case of RCC structural framework of column and beams with partition brick walls is used for construction, the columns and beams show unsightly projections in room interiors.
4
External finishes.
Cement plastered brickwork, painted with cement – based paint. Finishing needs painting every in three years.
5
Useful carpet Efficiency around 83.5%
3
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REMARKS
Superior. In – Situ casting of whole structure and transverse walls done in a continuous operation, using controlled concrete mixers obtained from central batching, mixing plants and mechanically placed through concrete buckets using crane and compacted in leak proof moulds using high frequency vibrators In this system, the walls and floors are cast together in one continuous operation in matter of few hours and in built accelerated curing overnight enable removal and re-use of forms on daily cycle basis.
Superior quality in “System housing”
System construction much faster.
is
The Room – Sized wall panels and the ceiling elements cast against steel plates have smooth finishing and the interiors have neat and clean lines without unsightly projections in various corners. The walls and ceilings also have smooth even surfaces, which only need colour/white wash Textured / pattern coloured concrete facia can be provided. This will need no frequent repainting.
Permanent facia finishes feasible with minor extra initial cost
Efficiency around 87.5%
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area as % of plinth area.
utilization of land for useful living space.
Consumption of basic raw materials Normal Cement.
6 Reinforcing Steel
Maintenance
7
Consumption somewhat more Although than that used in conventional greater structures. consumption strength and durability is also more Reinforcing steel required is less as compared to the in situ construction as RCC framework uses brick wall as alternative
In maintenance cost, the major expenditure is involved due to : • Repairs and maintenance of plaster of walls / ceiling etc. • Painting of outer and inner walls. Leakages due to plumbing and sanitation installation.
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It may, however will be slightly more than corresponding load – bearing brick wall construction for which, requirements of IS 456 have to be followed for system housing.
The walls and ceiling being smooth and high quality concrete repairs for plastering and leakage’s are not at all required frequently.
Steel requirement is more, as it is required for the shear wall construction. But shear wall construction increases safety against earthquake. It can be concluded that maintenance cost is negligible.
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3.0 MIVAN: - A Versatile Formwork The system of aluminum forms (MIVAN) has been used widely in the construction of residential units and mass housing projects. It is fast, simple, adaptable and cost – effective. It produces total quality work which requires minimum maintenance and when durability is the prime consideration. This system is most suitable for Indian condition as a tailor–made aluminum formwork for cast–in–situ fully concrete structure.
Background Mivan is basically an aluminium formwork system developed by one of the construction company from Europe. In 1990, the Mivan Company Ltd from Malaysia started the manufacturing of such formwork systems. Now a days more than 30,000 sq m of formwork used in the world are under their operation. In Mumbai, India there are number of buildings constructed with the help of the above system which has been proved to be very economical and satisfactory for Indian Construction Environment. The technology has been used extensively in other countries such as Europe, Gulf Countries, Asia and all other parts of the world. MIVAN technology is suitable for constructing large number of houses within short time using room size forms to construct walls and slabs in one continuous pour on concrete. Early removal of forms can be achieved by hot air curing / curing compounds. This facilitates fast construction, say two
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flats per day. All the activities are planned in assembly line manner and hence result into more accurate, well – controlled and high quality production at optimum cost and in shortest possible time. In this system of formwork construction, cast – in – situ concrete wall and floor slabs cast monolithic provides the structural system in one continuous pour. Large room sized forms for walls and floors slabs are erected at site. These forms are made strong and sturdy, fabricated with accuracy and easy to handle. They afford large number of repetitions (around 250). The concrete is produced in RMC batching plants under strict quality control and convey it to site with transit mixers. The frames for windows and door as well as ducts for services are placed in the form before concreting. Staircase flights, façade panels, chajjas and jails etc. and other pre-fabricated items are also integrated into the structure. This proves to be a major advantage as compared to other modern construction techniques. The method of construction adopted is no difference except for that the sub – structure is constructed using conventional techniques. The super–structure is constructed using MIVAN techniques. The integrated use the technology results in a durable structure.
3.1 Modular Formwork The formwork system is precisely-engineered system fabricated in aluminium. Using this system, all the elements of a building namely, load bearing walls, columns, beams, floor slabs, stairs, balconies etc can be constructed with cast in place concrete. The resulting structure has a good quality surface finish and accurate dimensional tolerances. Further, the construction speed is high and the work can be done in a cost effective manner. The modular nature of the formwork system allows easy fixing and removal of formwork and the construction can proceed speedily with very little deviation in dimensional tolerances. Further, the system is quite flexible and can be easily adapted for any variations in the layout. The availability of concrete from ready mix concrete facility has augured well for the use of this work system. However, the proliferation of RMC facilities in the cities in
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India and the willingness to use mechanized means of transport and placing of concrete, the use of aluminium formwork system has received a boost. The quality of the resulting concrete is found to be superior. Structurally speaking, the adoption of the closed box system using monolithic concrete construction has been found to be the most efficient alternatives. The stresses in both the concrete and steel are observed to be much lower even when horizontal forces due to wind or earthquake are taken into consideration. The formwork system can be used for construction for all types of concrete systems, that is, for a framed structure involving column beam –slab elements or for boxtype structure involving slab-walls combination.
3.2 FORMWORK – COMPONENTS: 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. The panels are manufactured in MIVAN’S dedicated factories in Europe and South East Asia. Once they are assembled they are subjected to a trial erection in order to eliminate any dimensional or on site problems. All the formwork components are received at the site whining three months after they are ordered. Following are the components that are regularly used in the construction. 3.2.1: -WALL COMPONENTS: 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
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FIG 3.1: WALL PANEL
2) Rocker: - It is a supporting component of wall. It is L-shaped panel having allotment holes for stub pin.
FIG 3.2: ROCKER
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3) Kicker: - It forms the wall face at the top of the panels and acts as a ledge to support
FIG 3.3: KICKER
4) Stub Pin: - It helps in joining two wall panels. It helps in joining two joints
FIG 3.4: STUB PIN 3.2.2:
- BEAM COMPONENTS:
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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 3.5: 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 3.6: PROP HEAD FOR SOFFIT BEAM. 3) Beam Soffit Panel: - It supports the soffit beam. It is a plain rectangular structure of aluminium.
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FIG 3.7: BEAM SOFFIT-PANEL
4) Beam Soffit Bulkhead: - It is the bulkhead for beam. It carries most of the bulk load.
FIG 3.8: - BEAM SOFFIT BULKHEAD
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3.2.3: DECK COMPONENT: 1) Deck Panel: - It forms the horizontal surface for casting of slabs. It is built for proper safety of workers.
FIG 3.9: - 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 3.10: -DECK PROP
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3) Prop Length: - It is the length of the prop. It depends upon the length of the slab.
FIG 3.11: - DECK PROP LENGTH
4) Deck Mid – Beam: - It supports the middle portion of the beam. It holds the concrete.
FIG 3.12: - DECK MID-BEAM
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5) Soffit Length: - It provides support to the edge of the deck panels at their perimeter of the room.
FIG 3.13: - SOFFIT LENGTH
6) Deck Beam Bar: - It is the deck for the beam. This component supports the deck and beam.
FIG 3.14: -DECK BEAM BAR
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3.2.4: 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 3.15: -INTERNAL SOFFIT CORNER 2) External Soffit Corner: - It forms the external corner between the components
FIG 3.16: -EXTERNAL SOFFIT CORNER
3) External Corner: - It forms the external corner of the formwork system.
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FIG 3.17: - EXTENAL CORNER 4) Internal Corner: - It connects two pieces of vertical formwork pieces at their exterior intersections. Fig 3.18
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FIG 3.18: - INTERNAL CORNERS
3.2.5: FORMWORKS ASSEMBLE: MIVAN aims in using modern construction techniques and equipment in all its projects. On leaving the MIVAN factory all panels are clearly labeled to ensure that they are easily identifiable on site and can be smoothly fitted together using the formwork
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modulation drawings. All formwork begins at a corner and proceeds from there. (Fig. No.3.19, Fig no 3.20).
FIG 3.19: - WALL ASSEMBLY DETAILS
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FIG 3.20: - BEAM ASSEMBLY DETAILS
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3.2.6: 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.
(Fig.No.3.21)
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. 3.2.7 EFFICIENT – QUICK STRIP PROP HEAD: One of the principal technical features which enables this aped to be attained using a single set of formwork panel is the unique V shaped a prop head which allows the ‘quick strip’ to take place whilst leaving the propping undisturbed. The deck panels can therefore be resumed immediately. (Fig.No.3.22). 3.3 CONSTRUCTION ACTIVITIES WITH MIVAN AS FORMWORK The construction activities are divided as pre – concrete activities, during concreting and post – concrete activities. They are as follows: 3.3.1 PRE – CONCRETE ACTIVITIES: 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. i.
All formwork should be cleaned and coated with approved realize agent.
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ii.
Ensure wall formwork is erected to the setting out lines.
iii.
Check all openings are of correct dimensions, not twist.
iv.
Check all horizontal formwork (deck soffit, and beam soffit etc.) in level.
v.
Ensure deck and beam props are vertical and there is vertical movement in the prop lengths.
vi.
Check wall ties, pins and wedges are all in position and secure.
vii.
Any surplus material or items to be cleared from the area to be cast.
viii.
Ensure working platform brackets are securely fastened to the concrete.
3.3.2 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: i.
Dislodging of pins / wedges due to vibration.
ii.
Beam / deck props adjacent to drop areas slipping due to vibration.
iii.
Ensure all bracing at special areas slipping due to vibration.
iv.
Overspill of concrete at window opening etc.
3.3.3 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.
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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: 3.3.4 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.
3.3.5 TRANSPORTING: There are basic three methods recommended when transporting to the next floor: i.
The heaviest and the longest, which is a full height wall panel, can be carried up the nearest stairway.
ii.
Passes through void areas.
iii.
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.
3.3.6 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.
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Fig 3.1: - Erection of Platform
Fig 3.2:- Striking of formwork
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Fig 3.3: - Positioning of Platform
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Fig 3.4: - Removal of kicker 3.4 SOFTWARE APPLICATION TO FORMWORK DESIGN
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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.
3.5 SITE MANAGEMENT The essence of the system is that it provides a production line approach in the construction industry. The laborers are grouped together to form small teams to carry out various tasks within a certain time frame such as, reinforcement, fabrication and erection, formwork erection, concreting etc. Scheduling involves the design and development of the work cycle required to maximize efficiency in the field. The establishment of a daily cycle of work, which when fully coordinated with different trades such as reinforcement fixing, mechanical services
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installation, and the placing of concrete, includes a highly efficient working schedule in the system, not just for formwork but for all parallel trades as well. Optimum use of the labour force is made by ensuring that each trade has sufficient work on each working day. Experienced site supervisors are sent to site to train supervisory staff and labour for proper handling of the equipment and to assist in establishing the desired work cycle. The disciplined and efficient handling of work ensures that all other trades follow in a united and predetermined manner. The improved coordination and construction management enables the equipment to be used at optimum speed and efficiency and speed of the output are outstanding. Thus a disciplined and systemized approach to construction is achieved. 3.6 SPEED OF CONSTRUCTION 3.6.1 Work cycle MIVAN is a system for scheduling & controlling the work of other connected construction trades such as steel reinforcement, concrete placements & electrical inserts. 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 hrs.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. On leaving the MIVAN factory 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: -
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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. 3.7 Design Aspects The comparison is done between buildings constructed by: i)
Conventional RC columns, beams, and slab construction (RC moment resisting framed structure) OR
ii)
RC load-bearing walls and slabs.
In the case of RC moment-resisting framed structures, the horizontal forces due to wind or earthquake are resisted by the frames resulting in the bending moments in columns to resist bending moment and vertical loads would be more than that required to resist vertical loads without bending moment. Similarly, additional reinforcement will be required in beams at supports. In the case of RC load-bearing walls, monolithic casting of slab along with RC walls results in a box type structure, which is very strong in resisting horizontal forces due to wind or earthquake. In view of large depth of shear walls, the resulting stresses due to bending moment and vertical loads are smaller and in many cases, concrete alone is capable of resisting these forces. On evaluating these alternatives, it is seen that the beam column frame system in i)
Performs poorly against earthquake forces compared to RCC wall and slab construction. Recent changes in the IS Codes, as well as recommended good practice demand provision of additional reinforcement comply with ductility requirements.
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ii)
The sizing and detailing of columns needed to be –that they are 20% stronger than beams they support.
3.8 Economics Comparative costs of building using load bearing wall and slab system and conventional framed system of column, beams, slab for the construction of a groundplus-seven building is given in Table 3.8.1. It can be seen that the total cost of groundplus-seven building using MIVAN System is Rs.5344/m² which is lower than that in conventional system is Rs.6034/m².( As calculated by Srinivaschar.P.H, July 2005). The cost per flat (or per m² built up area) using MIVAN shuttering system depends upon the number of repetition and period of completion of the project. As the formwork can be reused over 250 times, the initial cost per unit of forming area is less when compared to traditional methods. The reduction of cost is also due to the elimination of brickwork and plaster and also due to reduction in time. The cost of the project gets substantially reduced due to shear wall construction. These are due to the reduced consumption of steel, masonry, and plaster even though the use of concrete decreases. For the same number of repetition, the cost will be less if the period of completion is longer. This is because for a shorter completion period, the area of formwork is more than required for longer completion period. Cost of formwork is illustrated in Table no.3.8.2. The aluminium formwork provides an integrated scaffolding system which reduces the cost of scaffolding requirements. The mechanical and electrical installation is simplified as conduits are embedded in the structure by precise engineering of outlets and service ducts. Thus, we can conclude that the overall cost of the project is lesser when compared to project using traditional methods of formwork.
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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 Period of const. Forming area Misc formwork Total formwork to be ordered Cost of formwork Two third of the loaded cost Profit & Overhead 15% Total Rs. Cost per flat, Rs
A 3 flats/day 23 months 741.9 55.5 797.4
Construction Speed B C 4 flats/day 5 flats/day 18.7 months 16.2 months 989.2 1236.5 55.5 55.5 1044.7 1292
D 6 flats/day 14.2 months 1483.8 55.5 1539
14353200 9568800
18804600 12536400
23256000 1550400
27707400 18471600
1435320
1880460
2325600
2770740
11004120 9825
14416860 12872
17829600 15919
21242340 18966
Note: Construction period is calculated as follows: Average 22 pouring of concrete are considered per month. About 3 months are required for mobilization and getting plinths ready. About 3 months are required for finishing. Cost of formwork = $ 360; dollar Exchange Rate = Rs50; No of flats = 1120 (Weight of aluminium formwork = 24 kg/m²).
3.9 QUALITY: High quality Formwork panels ensure consistency of dimensions. On the removal of the formwork mould a high quality concrete finish is produced to accurate tolerances and verticality. The high tolerance of the finish means that no further plastering is required. Typically a 3mm to 4mm skin coat is applied internally prior to finishing and a 6mm build up coat prior to laying tiles. Care must be taken so that the concert and in particular the enforcement does not become contaminated due to excessive or negligent application of the releasing agent. 4.1 The Advantages of this system are:The MIVAN formwork is specifically designed to allow rapid construction of all types of architectural layouts.
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1) Total system forms the complete concrete structure. 2) Custom designed to suit project requirements. 3) Unsurpassed construction speed. 4) High quality finish. 5) Cost effective. 6) Panels can be reused up to 250 times. 7) Erected using unskilled labor.
Quality and speed must be given due consideration along with economy. Good quality construction will never deter to projects speed nor should it be uneconomical. In fact, time consuming repairs and modifications 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 the initial cost is high.
4.2 LIMITATION OF MIVAN FORMWORK: 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.
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7) Due to box-type construction shrinkage cracks are likely to appear. 8) Heat of Hydration is high due to shear walls.
4.3 REMIDIES 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 boxtype 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. 5.0 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 MIVAN FORMWORK:SPHAGETTI at KHARGHAR Location:
Navi – Mumbai.
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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.
5.1 DISCUSSION
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.
6.1 CONCLUSION:
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The task of housing due to the rising population of the country is becoming increasingly monumental. In terms of technical capabilities to face this challenge, the potential is enormous; it only needs to be judiciously exploited. Civil engineers not only build but also enhance the quality of life. Their creativity and technical skill help to plan, design, construct and operate the facilities essential to life. It is important for civil engineers to gain and harness the potent and versatile construction tools. Traditionally, construction firms all over the world have been slow to adopt the innovation and changes. Contractors are a conservative lot. It is the need of time to analyze the depth of the problem and find effective solutions. MIVAN serves as a cost effective and efficient tool to solve the problems of the mega housing project all over the world. MIVAN aims to maximize the use of modern construction techniques and equipments on its entire project. We have tried to cover each and every aspect related to aluminium (MIVAN) form construction. We thus infer that MIVAN 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. List of figures Figures
Page
Fig 1.1 Prefabricated Technology…………………………………………….……….9 Fig 1.2 Tunnel Technology……………..…………………………………….……….9 Fig 1.3 Outinard Technology……………………………………………………..….10 Fig 1.4 Mascon Technology………………..……………………………………...…10
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Fig 2.1 Staircase under Traditional formwork arrangement……..…………………..13 Fig 2.2 Typical steel formwork system………………………………………………13 Fig 2.3 Aluminum formwork for wall ……………………………………………….13 Fig 2.4 Precast elements……………………………………………………………...14 Fig 2.5 Hydraulic jack devices………………………………………………………..14 Fig 2.6 VSL formwork………………………………………………….…………….15 Fig 3.1 Wall Panel…………………………………………………………………….25 Fig 3.2 Rocker………………………………………………………………….……..26 Fig 3.3 Kicker…………………………………………………………………………26 Fig 3.4 Stub pin………………………………………………………………………..27 Fig 3.5 Beam side panel……………………………………….………………………27 Fig 3.6 Prop head for soffit beam………………………..……………………………28 Fig 3.7 Beam soffit panel……………………………………..……………………….28 Fig 3.8 Beam soffit bulkhead……………………………….…………………………29 Fig 3.9 Deck Panel………………………………………….…………………………29 Fig 3.10 Deck prop……………………………………………………………………30 Fig 3.11 Deck prop length…………………………………………………………….30 Fig 3.12 Deck mid-beam………………………………………………………………31 Fig 3.13 Soffit length………………………………………………………………….31 Fig 3.14 Deck beam bar……………………………………………………………….32 Fig 3.15 Internal soffit corner………………..………………………………………..32 Fig 3.16 External soffit corner…………………………………………………………33 Fig 3.17 External corner……………………………………………….………………33 Fig 3.18 Internal corner………………………………………………………………..34 Fig 3.19 Wall assembly details…………………………………………………..……35 Fig 3.20 Beam assembly details………………………………………………………36 Fig 3.3.1 Erection of platform………………………………………………………...41 Fig 3.3.2 Striking of formwork……………………………………………………….42 Fig 3.3.3 Positioning of platform………………………………………………….….43 Fig 3.3.4 Removal of kicker…………………………………………………….……44
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List of Tables Tables
Page
Table 1.1- Total population and percentage of population in unauthorized construction………………………………………………………………5 Table 1.2- Shortage of housing in India ………………………..……………………6 Table 2.1- Comparison of Aluminium formwork with Conventional type…………..21 Table 3.1- Detailed time schedule for twenty four hours ……………………………46 Table 3.2- Productivity of MIVAN forms in 4 days………………………………....47 Table 3.8.1- Cost of comparison of Conventional & MIVAN……………………….49 Table 3.8.2- Effect of construction speed on the cost of flat………………...……….50 References: 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 7. Raymond., W., W., M., “(2001)”. “Conditions and Constraints in the formwork systems for the complex High Rise buildings – with cases from HongKong”. July 2001, pp 2-6. 8. Shah., A., B., “(2005)”. “Large panel precast construction for speed and economics”. “Indian Concrete Journal”, July2005, Volume 79, pp. 47-54. 9. Shah., Ketan., “(2005)”. “ Modular formwork for faster, economical and quality construction”. “Indian Concrete Journal”, July 2005, Volume 79, pp 22-26.
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10. Telang., S., R., “(2005)”. “ Providing transit shelter to project affected people”. “Indian Concrete Journal”, July2005, Volume 79, pp. 55-59.
DISCUSSION WITH EMINENT EXPERTS: 1. Mr. Manohar R. Kharache, Executive Engineer, CIDCO. 2. Mr.Vikas Damle, Deputy Manager, ACC-RCD, Thane. 3. Mr. Ankur Jadhav, Site Engineer Spaghetti, L&T ECC. 4. Mr. Naik, Site Engineer Spaghetti, CIDCO.
WEB SITE CONSULTED: 1. 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) 7. MASCON- (Components, Assembly, Case studies) URL (www.mascon.com)
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RIT, ISLAMPUR
Mivan-A Versatile Formwork
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RIT, ISLAMPUR