Use of monitoring data to update performance predictions of supported excavations

Successful use of monitoring data to update performance predictions of supported excavations depends equally on reasonable numerical simulations of performance, the type of monitoring data used as observations, and the inverse analysis techniques used to minimize the difference between predictions and observed performance. This paper summarizes each of these factors and emphasizes their inter-dependence. Numerical considerations are described, including the selection of the type of finite element formulation, the initial stress conditions with emphasis on urban environments, the importance a reasonable representation of the construction process, and factors affecting the selection of the constitutive model. Monitoring data that can be used in conjunction with current numerical capabilities are discussed and a gradient-based inverse analyses technique that has been successfully used to update predictions of lateral ground movements measured close to support walls is summarized. Examples from application of these techniques from case studies are presented to illustrate the capabilities of this approach.