A Review on Modes of Failure and Factors affecting the Strength of Brick Masonry

Abstract

Abstract: The strength of masonry depends upon the strength of masonry units, mortar and the bond between them. The strength of the component materials is defined by standardized tests, which don’t necessarily reflect the state of stress in the component material in brickwork, but serve as index values in the selection of design stresses. This is only an empirical approach, which provides an acceptable basis for the structural design of brickwork. The approach is not altogether satisfactory as it gives little insight into the behavior of the brick mortar composite Research work has shown that the following factors are of importance in determining the compressive strength of brick masonry. These are strength of unit, geometry of unit, strength of mortar, deformation characteristics of unit and mortar, joint thickness, suction of units, water retentivity of mortar and brick work bonding. Some of these factors, such as unit characteristics are determined in the manufacturing process, while others such as mortar properties are subjected to variations in constituent materials, proportioning, mixing and accuracy of construction. It was concluded that the behavior of grouted unreinforced brick masonry panel was isotropic and the orientation of bed joint has no significant role in the failure criterion. Whereas the ratio of the horizontal to the vertical load has significant influence on the failure mode of clay bricks and hollow clay brick layers of panels. Also it was observed that the masonry strength under equal biaxial compression is higher by about 36% on average than that under uniaxial compression.