Geotechnical Designs Gone Wrong — Lessons Learnt

Since the occurrence of several apartment building problems in recent years, government agencies have taken steps to promote a greater level of building design and construction compliance. For example, the Design and Building Practitioners Regulation 2021 (NSW) that came into force on 1 July 2021 requires engineering reports associated with Class 2 buildings (i.e. residential or part-residential) to be signed by a registered Design Practitioner with relevant qualifications and skills, and a completion compliance certificates to be issued by the various design discipline practitioners of the project and submitted by a registered Professional Engineer.

Perhaps time will tell, but the author is sceptical that the introduction of additional government regulations would necessarily reduce the number of failures in geotechnical practice. The author believes that it may be helpful for the industry to publish more case studies on geotechnical failures so that lessons can be learnt from common mistakes.

This paper outlines some common geotechnical design problems encountered based on 50 or so expert witness cases that the author has been involved in during the last decade, and provides a generalized discussion on some of the most prevalent geotechnical design issues and the lessons learnt.