Bootstrap method for characterizing the effect of uncertainty in shear strength parameters on slope reliability

• Published in: Reliability engineering & system safety 2015-08, Vol.140, p.99-106
• Main Authors: Li, Dian-Qing, Tang, Xiao-Song, Phoon, Kok-Kwang
• Format: Article
• Language: English
• Subjects: Bootstrap method; Confidence intervals; Criteria; Mathematical models; Probability distribution; Reliability index; Safety; Shear strength; Slope reliability; Slopes; Standard deviation; Uncertainty
• ISSN: 0951-8320; 1879-0836
• DOI: 10.1016/j.ress.2015.03.034

This paper aims to propose a bootstrap method for characterizing the effect of uncertainty in shear strength parameters on slope reliability. The procedure for a traditional slope reliability analysis with fixed distributions of shear strength parameters is presented first. Then, the variations of the mean and standard deviation of shear strength parameters and the Akaike Information Criterion values associated with various distributions are studied to characterize the uncertainties in distribution parameters and types of shear strength parameters. The reliability of an infinite slope is presented to demonstrate the validity of the proposed method. The results indicate that the bootstrap method can effectively model the uncertain probability distributions of shear strength parameters. The uncertain distributions of shear strength parameters have a significant influence on slope reliability. With the bootstrap method, the slope reliability index is represented by a confidence interval instead of a single fixed index. The confidence interval increases with increasing factor of slope safety. Considering both the uncertainties in distribution parameters and distribution types of shear strength parameters leads to a higher variation and a wider confidence interval of reliability index. •A bootstrap method is proposed to characterize effect of uncertainty on reliability.•An infinite slope is studied to demonstrate validity of bootstrap method.•The bootstrap method can effectively model uncertain probability distributions.•Slope reliability index is a confidence interval instead of a single fixed index.•Confidence interval of reliability index increases with increasing factor of safety.