ABSTRACT
This chapter discusses the behaviour of masonry under all the types of action, an understanding of which is an essential prerequisite for successful structural design. Masonry is not an ideally elastic material because it is full of minor imperfections such as microcracks in the bond layers and because the differences between the unit and mortar stiffnesses and Poisson’s ratios produce high local strains at the interface, which results in non-linear behaviour. Like any structural material, masonry must resist loads or forces due to a variety of external influences and in various planes. Any masonry under compressive stress also resists bending since the compressive pre-stress in the wall must be overcome before any tensile strain can occur. In bonded masonry the overlapping of the units inhibits the growth of cracks, which are generated in the vertical joints by tension, until the stress exceeds the tensile resistance of the units.
