TARA Ferrocement technology package for roofing uses state of-the-art design principles to manufacture reinforced shells. Commonly called channels they are produced on specially designed vibrating tables and profiled moulds. The production system is uniquely tailored to provide special end details, consistent shape and thickness; all crucial for high performance the channels made with an optimised proportion of cement, sand and water. They have a very high density, are impervious to penetration of water and provide high structural strength. Ferrocement roofing technology offers a viable alternative to conventional flat roofing systems such as reinforced cement concrete, reinforced brick cement, sand stone, etc. in both rural and urban areas of the country.
Ferrocement roofing channels are manufactured using designed mix of cement, sand and water to give high strength mortar that is reinforced with a layer of galvanised iron chicken wire mesh of 22 gauge and tor steel bars of 8-12 mm diameter provided in the bottom nibs of the channel. Ferrocement roofing channels can be safely transported for the application after a curing period of 14 days.
The moulds are cast using the designed mortar and the filled moulds are lifted from the vibration table using specially designed lifting frame and steel tongs. Before demoulding, these moulds are kept undisturbed for 24 hours till the freshly cast channels achieve minimum strength. Finally these channels are stacked for water curing for minimum 14 days before they can be used for construction.
Advantages of TARA Ferrocement channels
|Specifications of the channel||Length - 3.05m and 4.6m (maximum upto 6.05 m) Clear bay width 0.75m, total bay width 0.83m Profiles as per rise of the arch - 290mm and 150mm|
|Annual production||3000 No. of Ferrocement channels|
|Land requirement||Total 2500m2 for casting, demoulding , curing, stacking and movement space,250 m2 of covered working space|
|Electricity requirement||10 KVA|
|No.of jobs created||10 (1 supervisor, 1 skilled, 8 unskilled)|
|Infrastructure cost for office and workshop (includes: Working shed, office space, cement godown, facilities-electricity and water)||Rs 240,000|
|Equipment (with 1machine, 10 No moulds) (vibrating table with vibrators, moulds, lifting frame, a pair of tongs and transfer trolley)||Rs 384,000|
|Gantry system cost (in a mechanized system)||Rs 125,000|
|Transportation and insurance (in India||Rs 12,000|
|Installation and know how transfer||Rs 50,000|
|Total (package with hydraulic machine)||Rs 8,11,000/- (US$ 16,220)|
|These cost do not include cost of land, as it varies considerably from place to place)|
Mr. Subroto Roy