We believe that the technology proposed by IIT Madras, and demonstrated recently by the construction of the 'GFRG demo building', has the potential to meet this challenge of providing rapid affordable mass housing.
Advantages over conventional buildings:
- High speed of construction: GFRG demo building with four flats in two storeys (total 1981 sq.ft.) built within a month!
- Less built-up area for the same carpet area: wall panels are only 124mm thick.
- Less embodied energy and carbon footprint: significant reduction in use of cement, sand, steel and water; recycling of industrial waste gypsum.
- Lower cost of structure: savings in materials; no plastering.
- Lower building weight (panels weigh only 43 kg/m2), contributing to savings in foundation and reduction in design for earthquake forces, particularly in multi-storeyed construction.
- Buildings up to 8-10 storeys can be designed using this load-bearing system, without the need for beams and columns.
- Excellent finishes of prefabricated GFRG panels - used for all the walls, floors and staircases, with minimal embedded concrete: no need for additional plastering.
The 'model housing apartment', comprising four flats in a two-storeyed building, has been constructed inside the IIT-M campus within a month at a finished cost that works out to Rs. 1250 per sq. ft. (including excellent finishes). The 'GFRG demo building' was inaugurated today by Sri TKA Nair, Advisor to Honourable Prime Minister of India, in the presence of Prof. Bhaskar Ramamurthi, Director, IIT Madras.
The panels are prefabricated and cut to desired sizes based on room dimensions with openings for doors and windows, thus making rapid construction possible. A panel has two skins of 15 mm thickness that are interconnected at regular intervals (250 mm) with 20 mm thick ribs. The cavities formed by these interconnections can be used for several purposes - filling with concrete, and laying electrical conduits and plumbing pipes.
GFRG panel - Filling the cavities with concrete
Filling the cavities with concrete increases the vertical load-carrying capacity almost tenfold, and inserting vertical steel bars in these cavities, contributes to their earthquake resistance. In a multi-storeyed building, the number of concrete-filled cavities and steel bars can be reduced at the higher floor levels. When used as floor slabs, reinforced concrete beams can be embedded and hidden in some of the cavities, as per the design. The overall weight of the structure and consumption of concrete comes down significantly. Conventional plastering is eliminated.
Reference : www.ndtv.com
Based on the research work carried out at IIT Madras, and the research reported elsewhere (Australia and China), Building Materials & Technology Promotion Council (BMTPC), Government of India, has accorded approval of GFRG panels for construction in India.