RESPONSE OF CONCRETE BLOCK MASONRY WALLS SUBJECTED TO IN-PLANE SHEAR AND FLEXURAL LOADS

This paper presents the results of a study onthe in-plane seismic performance o f full-scale unreinforced concrete block masonry (URCBM ) walls, commonly constructed in Iran, usin g numerical simulation. Considering limited studies in this field, an experimental research with the objective of investigating the behaviour of these walls under in-plane lateral loading, is first performed on small-scale masonry wall. The numerical modeling based on micr o-modeling, is then developed and calibrated to present similar inelastic load-displacement response and failure mode to those of the tested specimens. After verifying the numerical model, a parametrical study is performed on 3D,full-scale dimensions URCBM wallshaving different aspect (height/length) ratios of 0.5, 0.75, 1, 1.5 and 2, and also with two different boundary conditions; cantilever (flexural b ehaviour) and fixed (purely shear behaviou r). The nonlinear static (pushover) analyses results show t hat the walls boundary conditions have a profo und effect on the lateral behaviour and mode of failure of m asonry walls. The failure mechanism of fixed end s walls is predominantly shear, whereas, failure in cantileve r walls is generally due to rocking.Also, the lateral capacity of walls decreases with increase of aspect rat io.

کلیدواژه ها:

Masonry Wall ، Concrete Block ، In-Plane Shear ، In-Plane Flexure ، Seismic Response