Innovation in Construction Technology
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.
Pre-cast and cast-in-situ are techniques that are used for quick construction. Pre-cast 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 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 semi-skilled 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.
“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.
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.
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.
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.
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.
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.
Mascon Technology. (Raymond, 2001)
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