A practical reliability assessment approach and its application for pile-stabilized slopes using FORM and support vector machine

Many uncertainties exist in pile-stabilized slopes which make their design substantially complicated. In this paper, a first-order reliability method (FORM) based on a support vector machine (SVM) and uniform design (UD) is proposed to investigate the reliability of a pile-stabilized slope. A deterministic model considering soil-pile interaction and using a strength reduction method based on the displacement criterion is employed to calculate the factor of safety and the corresponding pile-bending moment. The uncertainties involved in both the soil and the stabilizing pile are taken into consideration in the proposed method. Two typical failure modes, namely the insufficient factor of safety of a pile-stabilized slope and the insufficient flexural bearing capacity of stabilizing piles, are investigated from a probabilistic viewpoint. The proposed method is illustrated with an artificial homogeneous slope and a real slope engineering case. The influence of stabilizing pile installation locations on the reliability results were studied. The sensitivity of random variability was also investigated. The results of the proposed method show high accuracy while having a smaller computational time requirement when compared with the polynomial response surface method. The case study of a real highway slope shows the feasibility of the proposed method applied to practical engineering problems.