Influence of Block and Mortar Strength on Shear Resistance of Concrete Block Masonry Walls

摘要

Data from seventeen masonry wall panel tests are presented. All of the walls are ungrouted, unreinforced, and constructed with hollow concrete block. The primary variables in the test series are block and mortar strength, but the applied vertical compressive stress and wall aspect ratio are also varied. The walls are built with either a 'high' strength block or a 'low' strength block having gross area unit strengths of approximately 1800 psi and 1300 psi, respectively. The mortar is either a Type S or Type N mortar and, for convenience, is identified as high and low strength mortar, respectively. Thirteen of the wall panels have nominal dimensions of 64 in. long x 64 in. high x 8 in. thick, but two of the walls are 96 in. long and the remaining two walls are 48 in. long. The applied net area vertical compressive stress is constant for a given test, but varies between 100 psi and 400 psi for tests in the series reported herein. The walls are tested in the NBS Tri-directional Test Facility using fixed-ended boundary conditions at the top and bottom of the walls. A vertical compressive stress is applied and maintained while in-plane lateral displacements are imposed at the top of the wall.