ABSTRACT
In lattice masonry (also known as hit and miss brickwork) the mortar perpend joints are left unfilled and the masonry units are spaced along the courses to leave a gap between adjacent units, allowing the passage of light and air through the wall. Regardless of whether this masonry is used in a loadbearing or nonloadbearing application, it must still be capable of spanning between supports to resist out-of-plane lateral loading to satisfy robustness requirements and to resist wind and/or earthquake actions and hence requires structural design. The Australian Standard AS3700: Masonry Structures (Standards Australia 2018) provisions for one way vertical bending can be applied in the case of lattice masonry by using a section modulus based on the net bedded area. However, the provisions for horizontal bending and two way bending require that the masonry be constructed with all perpends completely filled and therefore lattice masonry falls outside the scope of AS3700 for horizontal and two way bending. Internationally, there also exists a lack of guidance for the structural design of this form of masonry.The paper describes an experimental study to assess the behaviour of unreinforced lattice masonry walls subjected to lateral out-of-plane pressure loading. Twenty one single leaf lattice masonry walls, of varying aspect (height: length) ratios, were constructed using extruded clay bricks (230 mm long x 110 mm wide x 76 mm high) and 1:1:6 (cement: lime: sand) mortar. Three walls were tested in one way vertical bending. Twelve walls, with varying overlap between units in adjacent courses, were tested in one way horizontal bending. Six walls, with two different aspect ratios, were tested in two way bending. The load versus deformation behaviour and the observed failure modes are reported.
