Proceedings on International Conference on Disaster Risk Management, Dhaka, Bangladesh, January 12-14, 2019 Page | 68 PERFORMANCE OF UNREINFORCED MASONRY WALLS IN SHAKING TABLE TEST M.A. Islam 1 , R. Ahsan 2 ABSTRACT Masonry is one of the oldest materials used and even now-a-days it is being used for the construction purpose in many countries. But performance of masonry structures in earthquake are very poor. Being a non- homogeneous material, the performance of masonry is very difficult to predict. Moreover, no dynamic loading test is done yet using Bangladeshi materials. Therefore, the objective of this research is to understand the dynamic behavior of unreinforced masonry (URM) walls made by indigenous materials. For this purpose, a half scale masonry room was constructed having dimension 1.83m x 1.52m (6’x5’) (length x width), height 1.52m (5’) and wall thickness 63mm (2.5”). Then the model was tested on an earthquake simulator. Dynamic testing was done using Imperial Valley Earthquake time history. The test shows that most of the cracks generated at the corner of the specimen. The model underwent an acceleration of 1.05g with severe cracks in the bed joints and head joints. The lateral force is compared with the prescribed shear force (capacity) as per Bangladesh National Building Code (BNBC 1993). The sample failed after reaching the capacity. Therefore, the code is conservative in terms of lateral load resisting capacity. Introduction Since Bangladesh situated in the high seismic zone, those buildings including the historical heritages are in very high risk. For simulation of structural behavior of such buildings, performance of embedded joints (head joints and bed joints) is important from the point of view of seismic design. Mostly vertical loading is considered during the design of masonry. While, the structural elements such as walls in URM buildings which were designed for vertical loads only, have to carry lateral load as well during an earthquake. As a result, those structures are vulnerable to earthquake because there is no ductility provision, which is necessary to withstand a certain level of earthquake. The heavy damage inflicted on masonry structures by some historic earthquake such as earthquake in 1987 in Srimangal, Bangladesh; 1997 in Umbria-Marche, Italy; 2005 in Kashmir, Pakistan; 2008 in Wenchuan, China; 2010 in Darfield, New Zealand; 2015 in Gorkha, Nepal all especially emphasized the high seismic vulnerability of unreinforced masonry structures. Therefore, complicated and intensive research on the seismic behavior of masonry structures is essential. Both experimentally and theoretically have gained much attention since the 1990s in different countries. A number of experimental researches e.g. In-plane tests (Fam et. al., 2002; Capozucca, 2011; Elgwady et. al., 2002), out of plane tests (Derakhshan and Ingham, 2008; Simsir et. al., 2004) and shake table tests (Elgwady et. al., 2002; Simsir et. al., 2004; Hanazato et. al., 2008; Ersubasi and Korkmaz, 2010) were conducted in different countries using their indigenous materials and testing equipment. But in Bangladesh, there are very few experimental evidence/results of lateral load resistance capacity of URM wall/buildings and no actual dynamic loading test have been conducted yet now. In Bangladesh, there are very few (Das, 2016; Asif et. al., 2017) experimental evidence of lateral load resistance capacity of URM wall and no actual dynamic loading test have been conducted. The exact crack pattern will, of course, depend on the wall boundary conditions and the aspect ratio of the URM elements. Seismic actions are bidirectional and the URM can perform in both in-plane and out-of-plane direction. Therefore, the objective of this research is to understand the overall dynamic behavior, in-plane and out of plane behavior of walls as well as the failure pattern of masonry structures with retrofit (using wire mesh) and without retrofit under shaking table tests in context of Bangladesh. Experimental Program Primary focus of this research program is to focus the dynamic behavior of half scale unreinforced masonry 1 Lecturer, BUET-Japan Institution of Disaster Prevention and Urban Safety, Dhaka-1000, Bangladesh 2 Director, BUET-Japan Institution of Disaster Prevention and Urban Safety, Dhaka-1000, Bangladesh Email of Corresponding Author- ai.buet08@gmail.com (URM) walls. For this purpose, a half scale URM room was constructed. This section describes the materials used for the specimen construction, construction, and testing procedure.