An efficient probabilistic back-analysis method for braced excavations using wall deflection data at multiple points

• Published in: Computers and geotechnics Vol. 85; pp. 186 - 198
• Main Authors: Qi, Xiao-Hui, Zhou, Wan-Huan
• Format: Journal Article
• Language: English
• Published: New York Elsevier Ltd 01.05.2017; Elsevier BV
• Subjects: Bayesian analysis; Bayesian updating; Braced excavation; Case histories; Data; Deflection; Dredging; Environmental monitoring; Excavation; Finite element analysis; Finite element method; Markov chain Monte Carlo method; Parameters; Probabilistic methods; Probability; Probability theory; Response surface method; Response surface methodology; Soil; Soils; Wall deflection data; China; Hangzhou China; Bayesian updating; Markov chain Monte Carlo method; Braced excavation; Finite element analysis; Response surface method; Wall deflection data
• ISSN: 0266-352X; 1873-7633
• DOI: 10.1016/j.compgeo.2016.12.032

This paper presents an efficient Bayesian back-analysis procedure for braced excavations using wall deflection data at multiple points. Response surfaces obtained from finite element analyses are adopted to efficiently evaluate the wall responses. Deflection data for 49 wall sections from 11 case histories are collected to characterize the model error of the finite element method for evaluating the deflections at various points. A braced excavation project in Hang Zhou, China is chosen to illustrate the effectiveness of the proposed procedure. The results indicate that the soil parameters could be updated more significantly for the updating that uses the deflection data at multiple points than that only uses the maximum deflection data. The predicted deflections from the updated parameters agree fairly well with the field observations. The main significance of the proposed procedure is that it improves the updating efficiency of the soil parameters without adding monitoring effort compared with the traditional method that uses the maximum deflection data.