SEISMIC STRENGTHENING OF UNREINFORCED MASONARY (URM) BUILDINGS

Abstract

This work examines the ability and feasibility of strengthening existing unreinforced masonry (URM) structures, built with locally available and used materials and constructed using local practices, using commercially of the shelf (CoTS) available Textile Reinforced Mortar (TRM) system. Forty masonry samples were prepared and tested for in-plane shear strength, out-of-plane bending strength parallel to bed joint and out-of-plane bending strength perpendicular to bed joint. The variations studied were the type of mortar, no of sides reinforced and the thickness of the mortar. Lime and cement based mortar were used along with a glass fiber - grid to strengthen the masonry; different layouts were selected and overall performances were compared with those of as-built ones. For in-plane shear strength testing, the samples were subjected to diagonal compression loading under displacement control in order to measure their in-plane deformation and strength properties, including the postpeak softening regime in view of seismic appi ications. Improvement of strength was observed during the investigations. For out-of-plane bending strength testing, three point bending test has been performed on the specimens to compare the flexural strength between various strengthening layouts, for cases parallel and perpendicular to bed joint. Increase in the load bearing capacity of the panels was observed for all the strengthened cases.