Multimodal reliability analysis of 3D slopes with a genetic algorithm

Summary Analyses of three‐dimensional slope failures can be elaborate because of the complexity owed to the geometry of the failure mechanism that needs to conform to an admissible kinematics of the slope collapse. This admissibility is imposed by the soil limit state condition, the normality plastic flow rule, and the boundary conditions. The kinematic approach of limit analysis is employed, and a rotational 3D slope failure is revisited. The study leads to the conclusion that some geometric constraints used in previous studies limit the range of admissible mechanisms resulting in overestimating stability factors. A set of results is presented that was obtained using an algorithm that allowed eliminating limitations present in previous studies. The largest improvements in the solutions were found for undrained failures of narrow slopes. For a 30° slope limited in width by the width‐to‐height ratio of 0.6, the stability factor calculated in previous studies overestimated the current calculations by nearly 39%. This overestimation is smaller for drained failures, and it drops significantly with an increase in the width of the failure mechanism.

Section: Introductionmentioning

confidence: 99%

mentioning

confidence: 99%

Intricacies in three‐dimensional limit analysis of earth slopes

Park

Michałowski²

2018

“…We can observe in recent years that more efforts have been devoted to the investigation of slope stability by using several novel efficient algorithms. For example, Tun et al 64 . used the genetic algorithm to find the optimal solution in the first‐order reliability method when evaluating the stability of a slope.…”

Section: Discussionmentioning

confidence: 99%

Efficient reliability analysis of slopes integrating the random field method and a Gaussian process regression‐based surrogate model

Zhu

Hiraishi

Pei

et al. 2020

Efficient evaluation of slope stability is a frontier in geo‐disaster prevention fields. While many slope stability evaluation methods, ranging from deterministic to probabilistic, have been proposed, reliability methods are particularly advantageous as they can account for uncertainties during slope stability evaluation. To address the problem of the low efficiency of direct Monte Carlo simulations and overcome the defects of the traditional response surface method, in this work, a novel probabilistic procedure that integrates a Gaussian process regression‐based surrogate model and the random limit equilibrium method for slope stability evaluation while accounting for the spatial variability of soil strength is proposed. The novel Gaussian process regression‐based surrogate model is efficiently used in the Monte Carlo simulation to reduce the number of calls for direct stability analysis of a slope with spatially varied soil strength. To verify the accuracy and efficiency of the proposed procedure, it was applied to three case studies: the first one is a slope in saturated clay under undrained conditions; the second one is a slope for which the friction angle and cohesion values are cross‐correlated; and the third one is a real slope with multiple soil layers. The results obtained from the comparisons with other methods confirmed the precision and feasibility of the proposed procedure.

“…A variety of approaches, such as the limit equilibrium method and the robust finite element method can be used to assess the stability of soil slopes. The numerical approaches such as finite element method can account for the progressive nature of the collapse and allow the failure mechanism to form without prescribing a particular shape.…”

Section: Introductionmentioning

confidence: 99%

“…[12][13][14][15][16][17] However, because of the highly variable nature of the suction, it is difficult to model its effect on the slope stability. [18][19][20][21] A variety of approaches, such as the limit equilibrium method 8,9,[22][23][24][25][26] and the robust finite element method [27][28][29][30][31][32][33][34][35][36] can be used to assess the stability of soil slopes. The numerical approaches such as finite element method can account for the progressive nature of the collapse and allow the failure mechanism to form without prescribing a particular shape.…”

Section: Introductionmentioning

confidence: 99%

3D stability of unsaturated soil slopes with tension cracks under steady infiltrations

Wang

et al. 2019

Summary Most classical approaches for evaluating the stability of soil slopes with cracks are performed under two‐dimensional (2D) condition. Three‐dimensional (3D) effect and suction‐induced effect of unsaturated soils are generally neglected in assessing the slope stability. This paper develops a 3D limit analysis method to evaluate the stability of an unsaturated soil slope with tension cracks under steady infiltrations. The boundary‐value problem is formulated based on the 3D rotational failure mechanism by taking the effects of suction, effective unit weight, and tension crack into account. A simplified method is proposed to calculate the work rate of unsaturated soil weight. A layer‐wise summation method is developed based on the divergence theorem to calculate the internal energy dissipation rate. Detailed discussions are conducted to investigate the effects of suction and Poisson's ratio on the stability of unsaturated soil slopes. Examples are given to illustrate the 3D effect, the suction‐induced effect as well as the effects of infiltration and water in cracks on the slope stability.