System reliability analysis of a slope stabilized with anchor cables and piles under seismic loading

Anchor cables and piles are commonly adopted to improve the stability of slopes under seismic loading. System reliability analysis (SRA) is essential for assessing the stability of slopes stabilized with anchor cables and piles (SSCPs) due to the various uncertainties and complex interactions in geological and geotechnical engineering. A new SRA approach for SSCPs was proposed by considering the effect of the failure of local anchor cables and piles on the system. The failure event of the SSCP was decomposed into multiple failure events with different numbers and sequences of failed anchor cables and piles. The system failure probability (P-SF) of the SSCP was calculated by summing the probabilities of all mutually exclusive failure events according to the total probability formulation. An example slope with weak layers in Yunnan Province, China, was employed to illustrate the proposed approach. The results show that this approach does not need to determine the correlation coefficients of multiple failure modes of SSCPs and is able to take into account the effect of the failure of the local anchor cables and piles on the SSCP system. The failure of the local anchor cables and piles significantly increases the failure probability of the remaining anchor cables, piles, and slopes due to stress redistribution, which may lead to cascading failures of anchor cables and piles failing one after another. The proposed approach provides a unique value for P-SF rather than a range with upper and lower bounds, which is more precise and convenient for assessing the system reliability of SSCPs. The failure probability of SSCPs could be underestimated if the failure of local anchor cables and piles is ignored.

Automated summary

Anchor cables and piles are widely used to improve the stability of slopes under seismic loading. System reliability analysis is crucial for assessing the stability of slopes stabilized with anchor cables and piles due to uncertainties and complex interactions. A new approach considering the effect of local anchor cables and piles failure on the system was proposed. The failure of local anchor cables and piles significantly increases the failure probability of the remaining anchor cables, piles, and slopes, leading to cascading failures. The proposed approach provides a precise value for system failure probability and is more convenient for assessing the reliability of slopes stabilized with anchor cables and piles.