Seismic response control of low-rise unreinforced masonry building test model using low-cost and sustainable un-bonded scrap tyre isolator (U-STI)

Abstract

Abstract Large stock of scrap tyres in waste disposal ground is a huge threat to the environment. In many civil engineering applications, potential of using scrap tyres have been explored in the last two decades. In this paper, effectiveness of Un-bonded Scrap Tyre Isolator (U-STI), as a seismic isolation system, has been evaluated by both experimental and numerical studies. Simple design approach of low-cost U-STI for seismic response control of the test model is outlined first. The mechanical properties of U-STI, under simultaneous action of horizontal cyclic displacement and vertical load, have been determined. Shake table testing of 1/5th scale two-storey masonry building supported on U-STIs has been carried out. Shake table testing confirmed that transmissibility of peak ground acceleration to the test model is reduced to a large extent and the peak floor accelerations are of the order of 12%–15% of the peak table accelerations, which establishes the effectiveness of the U-STI in controlling the seismic response of the test model. Results of the numerical analysis of the test model, using SAP 2000 v.19, have been validated by the experimental results. The U-STIs have been modelled using multi-linear pivot hysteretic plasticity model. Comparison of acceleration and displacement responses at various floor levels obtained from numerical analysis is done with that obtained from shake table tests. Results from the numerical tests are found to be in reasonably good agreement with those obtained from the experimental tests under the action of considered ground motions. It is concluded from the study that low-cost U-STIs are effective in reducing the seismic response of low-rise masonry building test models.