Earthquake Resistant Masonry Structures

Abstract

Brick and Brick masonry have been used extensively in building construction for many centuries and continues to dominate as the commonly used construction material either as a load bearing or as a filler wall. In masonry buildings, the ordinarily occurring vertical loads do not pose much of problem, but the lateral loads are matter of great concern and need special consideration in design of buildings. These lateral forces can produce the critical stress in a structure. The lateral force may cause three types of failure in the building viz. failure due to bending, due to overturning moment and due to sliding of the floor. Moreover the other criteria that should be taken care is of stability. It depends on many factors viz. geometry of the building, various elements of building like buttresses, cross walls etc. It is not only the analysis method that should be taken in consideration but also the other aspects that are described above. It is therefore necessary that methods should be evolved for designing and incorporating suitable features in masonry buildings to render adequate earthquake resistance and not earthquake proof. This report deals with the study carried out to understand the analysis and design of the masonry structures, providing an alternate to take the stresses by using vertical bars and weld mesh, application of earthquake resisting features in them and designing of multistory masonry buildings. Various case studies are taken making different combinations of wall thickness at different storey level. This report also includes experimental work carried out to determine the properties of brick and brick masonry under compressive loads. PRISM Test for masonry is carried out for different mortar proportions viz. 1:4, 1:5 and 1:6 using different layers of bricks i.e. 3, 6, 7 and 8 and incorporating different cases such as unplastered, plastered and reinforced samples. Compressive strength of masonry, stress strain relationship, modulus of elasticity etc parameters are studied.