Introduction

In the past, when design provisions were lacking, wall panels were usually taken as non-load-bearing. Due to the increased acceptance of precast techniques in building construction and a trend towards reinforced concrete core structures, walls have now become popular as load-bearing elements.

A wall is a vertical planar continuum with a thickness much smaller than its height or length. If a wall is short, with a length of the same order as the thickness, it can be treated as a column. In fact, AS 3600-2009 (the Standard) defines a wall as an element wider than three times its thickness. Otherwise the element is considered to be a column.

Walls are normally supported at the bottom end by a floor system and at the top end by a roof structure or another floor. Or a wall may be freestanding. Depending on the chosen structural system, walls may be supported on either or both sides by interconnecting walls or other structural elements. Consequently, a wall may act like a column, a beam cantilevered at one end or a slab standing vertically. Figure 10.1(1)a depicts a wall under vertical in-plane and lateral bending loads; Figure 10.1(1)b shows a wall that is under combined in-plane vertical (axial) and horizontal (shear) forces. At times a wall may be subjected to simultaneous axial, bending and shear forces.