Masonry Materials in Compression

The strength of masonry in compression, tension and shear has been the subject of systematic investigation over a very considerable period. As masonry structures are primarily stressed in compression, there has naturally been a concentration of interest in the resistance of the material to this type of loading, and many investigations have been carried out with a view to establishing the relationship between available unit types and materials, and a variety of mortar mixes. These tests have formed the basis for the masonry strengths used in structural design codes, and in order to reduce the almost unlimited range of unit and mortar combinations to manageable proportions, tables of basic compressive strength have been evolved in which the principal variables are the unit compressive strength and the mortar mix. The strengths of the component materials are defined by standardised tests, which do not necessarily reproduce the state of stress in the component material in service, but which serve as index values in the selection of design stresses.