AN EXPERIMENTAL STUDY ON THE RETROFITTING OF UNREINFORCED MASONRY SPECIMENS WITH ECC AND AFRP SHEET

摘要

It has been proved through past earthquake experiences that unreinforced masonry (URM) structures are not able to resist seismic loads and in order to reduce the serious damages caused by earthquakes, they should be considered for retrofitting. Incapability of lateral load resisting walls is mostly responsible for the collapse of URM structures around the world. In this research work, compressive and monotonic shear tests such as shear triplet and diagonal compression have been conducted on the specimens rehabilitated with engineered cementitious composite (ECC) overlay and aramid fiber reinforced polymer (AFRP) sheet. ECC with multiple fine cracks is a cement-based composite material which exhibits a high tensile strength and strain - hardening behavior. Also FRP products are well known for their retrofitting potential and as the present study, in order to eliminate the debonding behavior of FRP which greatly limits its efficiency, confining bands were utilized. The efficiency of both retrofitting methods were evaluated and discussed based on the test results. As a result, it was found out that the shear strength and deformation capacity of URM improved considerably.