Reliability analysis and updating of excavation-induced ground settlement for building serviceability evaluation

As part of the investigation of the serviceability reliability of a braced excavation system, KJHH model has recently been developed for estimating wall deflection and ground surface settlement in the braced excavation. In this study excavation-induced settlement determined by the KJHH model is used as an indicator to assess the serviceability reliability of adjacent buildings. The calculated settlement, considered as the load in the context of reliability analyses in this study, is compared with the tolerable limits of settlement proposed by Skempton and MacDonald (1956), considered as the resistance herein. The reliability of the building against "damage" (defined herein as the violation of serviceability requirements, or specifically in this case, whenever resistance is less than load) is analyzed during the design phase. Further, with the proceeding of excavation during the construction, observed settlement is used to update the KJHH model, and the predictions of settlement at subsequent stages are updated accordingly. Copyright ASCE 2007.