Low Cost Sliding Isolators for Developing Countries

An economic hybrid base isolation system in the form of friction pendulum system (FPS) and pure friction (PF) sliding isolators is proposed. The effect of ground motion on the behaviour of a G+3 RC building mounted on hybrid isolators as well as on other support conditions are investigated analytically by using synthetic accelerograms that is compatible with the design spectrum of Indian standard (IS 1893 (Part 1): 2002) corresponding to the level of maximum considered earthquake in the most vulnerable seismic zone (PGA=0.36g). It is estimated that an average reduction of around 78% in maximum absolute roof acceleration is achieved with the combined sliding isolators compared to the conventional fixed base support which is at the cost of maximum relative base sliding displacement (average 32mm). The change in position of the isolators has almost the same results. It is also observed that the response reduction in roof accelerations for the FPS and Roller is at parity with that of FPS and PF (within 3%) hybrid isolators. Hence, the proposed hybrid system, i.e. FPS when combined with PF isolators can be economically and effectively used for developing countries without any residual displacement.