performance enhancement of URM wall retrofitted using ECC

Abstract

In order to performing remodeling or charge the usage of building, unreinforced masonry walls which used commonly in apartment as structural or non-structural element need to have reliable performance of building. Onetechnique to enhance or recover lateral resistance of these structures is to retrofit the masonry walls using shotcrete. However, using normal concrete as shotcrete material, cannot improve ductility and may cause brittle failure at wall-frame or slab connection. However, recent study for new materials, such as ECC or UHPC, can solve these problems increasing ductility and toughness of concrete. In this study, we use sprayed ECCs for retrofitting of unreinforced masonry wall. ECCs can be designed to work in conjunction with existing walls to increase both strength and ductility for in-plane behavior of the unreinforced masonry walls, And this may change non-structural masonry wall to structural wall. To ensure that this technique will perform its intended purpose, in-place lateral loading test and FEM analysis was performed. The results of lateral quasistatic testing of two retrofitted URM will compared to non-retrofitted one in this study. Two retrofitted walls are consisted of just sprayed and anchored to wall base, RTM-ECC and have wiremesh, same dissipation capacity compared to non-retrofitted specimen. Specimen RTM-ECC show stiff strength degradation however, RTM-ECC-WM show slow degradation of wall capacity because of the load transferring effect of wiremesh.