抄録
The present study deals with the earthquake disaster reduction by the development of new composite material to mitigate the collapse of unreinforced masonry structures (URM) in urban and rural areas in developing countries. Collapse of unreinforced masonry walls causes a large number of human causalities due to a strong ground motion. Masonry walls are relatively strong for in-plane shear and much weaker in out of plane direction resulting collapse of masonry structure. Being highly expensive, FRP is a strong material and can significantly increase the out of plane bending strength of masonry walls. Being an expensive material, FRP exhibits a highly catastrophic brittle failure under extreme loading leaving no warning and evacuation time for residents. On the contrary, polypropylene band (PP-band) is a cheap material with much larger ductility and holding capacity to avoid sudden failure, caused by the breaking of wall into small fragments which has been found as a major cause of causalities. In this study, an attempt has been made to find a composite material by using FRP and PP-band to increase the shear capacity and to avoid the catastrophic brittle failure of masonry walls under strong ground shaking. In order to achieve required objectives, out of plane load tests have been carried out using six masonry wallets consisting of three non-retrofitted masonry wallets, PP-band retrofitted masonry wallet, FRP retrofitted masonry wallet and FRP+PP-band retrofitted masonry wallet. Behavior of wallets has been carefully observed in terms of peak strength, deflection and deformation capacity. It has been found that retrofitting of masonry walls using FRP and PP-band is much viable solution as compared to conventional retrofitting techniques because FRP+PP-band reduced the overall cost of retrofitting due to confining and holding effect of PP-band which is a very low cost material.
