Abstract

The geotechnical structures are usually designed using the element-by-element methods rather than the systems-based approaches. A large number of failure case histories of geotechnical structures have occurred in recent years although they have sufficient factor of safety. The designed geotechnical structures may lack of integrity and enough redundancy. The local failure of one geotechnical structural element may result in a chain reaction that causes other adjoining elements to fail in a domino effect, which in turn cause widespread structural failure or even collapse. The system performance concept calls for the geotechnical system to have enough robustness and redundancy to prevent from collapses or failures induced by the localized damage or weakness. It is the duty of the geotechnical engineers to consider the environment-friendly, cost-effective and socially-acceptable choices for the design and construction of geotechnical structures. This lecture will briefly introduce the concept of system performance in geotechnical engineering. Emphasis of letting geotechnical systems have enough robustness and redundancy is performed to prevent them from collapses or failures induced by the local damage or weakness. Several case histories of excavations, tunneling, and column-supported embankments will be analyzed in this lecture. The control methodologies to optimize the design and improve the system safety performance will also be presented.