Ductility of steel bars provide earthquake resistance
Concrete which is just made up of cement, sand and water is likely to break when it is stretched or twisted even by a small degree. This is because it has very low tensile strength. But when steel bars of optimum ductility goes into this concrete, they indirectly attain a tensile strength. “Buildings built with optimum ductilitay steel bars would be able to withstand mild tremors and earthquakes. ” says Reji Zachariah a Structural Engineer. He also adds that such building may shake or tremble a bit, but would never collapse when earthquakes of small-medium scale strikes. Such building would have the necessary ‘flexibility’ and would easily recover to their former state. This is because they have ductile TMT steel in their structure. On the other hand, buildings built with ordinary steel bars can only be left to their fate.
Experienced architects say that some regions of Kerala are prone to seismic attacks. In such areas, a ‘framed’ construction style can be adopted. The concrete pillars, beams and ceiling are first constructed and the walls are built in between the pillars. This would endow a flexible yet binding strength to the overall structure
The Bureau of Indian Standards (BIS) has classified five seismic zones for the entire country as per their intensity. Kerala falls in the Zone 3 and buildings constructed in this zone should ideally follow the recommendations of BIS.
Quality TMT steel has optimum ductility
Original TMT steel bars are manufactured with advanced technological processes on modern rolling mills. They possess optimum ductility and can be bent as per the mason’s requirement. On the other hand, spurious quality steel bars would break on bending, because they are not made with advanced technologies. They may carry a TMT label but would not have any properties of an original TMT steel bar.
TMT steel bars of optimum ductility are even suitable when two steel bars have to be welded and joined together.
Ordinary steel bars are mostly manufactured from old ships, railway tracks and so on. Hence they may contain impurities. These impurities reduce its quality and make it corrosive. Whereas, original TMT steel bars like METCON are not only less corrosive but do not easily wear out too. The unique rib pattern on their surface helps them to have a firm grip on the concrete. This in turn would help in the stability of the building. TMT steel bars also have the ability of withstanding high temperatures upto 6000 C.