Buy it, use it cautiously, but always verify against modern geotechnical advice and international best practice.
This document is not the Standard itself but the explanatory companion published by Standards Australia. 1. Executive Summary The AS 1170.4 Commentary is an essential, albeit non-mandatory, companion to the Australian Standard for earthquake loading. While the main Standard (AS 1170.4) provides the prescriptive formulas and limit states, the Commentary provides the why —offering background, derivations, and practical guidance for structural engineers. For anyone designing structures in Australia’s seismic zones (particularly Region III, e.g., Adelaide, parts of WA, and the Snowy Mountains), this document is as critical as the Standard itself. as 1170.4 commentary