L. R. BAKER
Deakin University, Geelong, Victoria
and S. J. LAWRENCE CSIRO, Sydney, N.S.W.
The first masonry code in Australia was published in 1963, by the Standards Association of Australia (S.A.A.) and applied to unreinforced concrete blockwork only. Although revised in 1967, metricated in 1977, and amended for lateral loading in 1983, it was, as a whole, essentially unchanged for over 20 years. A brickwork code first published in 1969, covered both unreinforced and reinforced brickwork. It too was virtually unchanged for 20 years. A third masonry code was added in 1983, to cover reinforced concrete blockwork. All of these codes were expressed in terms of permissible stresses and because of some conflicting provisions tended to cause divisions within the masonry industry.
It was decided in 1982 to revise these separate standards. The resulting code, AS 3700, was published in late 1988, and is a significant advance in that, for the first time, it covers all types of masonry in a single document and adopts the limit state approach to design. Areas of the code which incorporate major changes from previous codes are compressive strength design, robustness, concentrated loading, design for fire, reinforced masonry, material strengths and procedures for quality control and site testing. In particular the design procedures for resistance to fire, allow limited extrapolation from test results and incorporate tables for simplified design based on material thickness for insulation and slenderness ratio for stability, and thus are a significant step forward from the previous codes and building regulations.