System reliability analysis for anchor-stabilised slopes considering stochastic corrosion of anchors: Fid-Bau Portal

System reliability analysis for anchor-stabilised slopes considering stochastic corrosion of anchors

Li, Lin / Liang, Robert Y. / Liu, Hanlong

In this paper, a methodology using Monte Carlo simulation method was developed in conjunction with the modified limiting equilibrium method of slices. Additionally, the time-dependent deterioration of bond capacity of corroding soil anchors was developed in this methodology due to the attack of chlorides. Uncertainties of anchor-related variables and soil parameters were considered using pertinent statistical descriptors. Furthermore, the inherent stochastic nature of the corrosion and degradation process for the anchor/slope system was identified and incorporated in the simulation. A PC-based software, C-UASLOPE, has been coded to allow for handling of complex slope geometry, soil profile and groundwater conditions. An illustrative example was presented to clarify the application of the C-UASLOPE software in modelling the deterioration process to aid in determining the system reliability. The importance of using a system reliability-based algorithm was illustrated by showing that the anchor/slope system may fail unpredictably during design life – even though the initial design results have a high degree of safety – if uncertainties of soil parameters, anchor force and the time-dependent stochastic corrosion process are not accounted for systematically.