Reliability analysis of three-dimensional reinforced slope considering the spatial variability in soil parameters

• Published in: Stochastic environmental research and risk assessment 2024-04, Vol.38 (4), p.1583-1596
• Main Authors: Wang, Yuke, Shao, Linlan, Wan, Yukuai, Chen, Hao
• Format: Article
• Language: English
• Subjects: Aquatic Pollution; Chemistry and Earth Sciences; Computational Intelligence; Computer Science; Correlation coefficient; Correlation coefficients; Earth and Environmental Science; Earth Sciences; Environment; Failure; Fields (mathematics); Geotechnical engineering; Math. Appl. in Environmental Science; Mathematical analysis; Monte Carlo simulation; Original Paper; Parameters; Physics; Probability Theory and Stochastic Processes; Reinforcement; Reliability analysis; Safety; Safety factors; Sliding; Slopes; Soil analysis; Soil strength; Statistics for Engineering; Three dimensional analysis; Two dimensional analysis; Waste Water Technology; Water Management; Water Pollution Control
• ISSN: 1436-3240; 1436-3259
• DOI: 10.1007/s00477-023-02636-5

Reliability analysis of reinforced slopes is crucial in geotechnical engineering. In this study, a procedure is proposed for calculating the reliability of three-dimensional reinforced slopes, taking into consideration the spatial variability of soil strength parameters. An ellipsoidal sliding surface is utilized as an approximate substitute for the actual sliding surface. The Karhunen–Loève (K–L) expansion method is employed to generate random fields. The safety factor calculations are based on the Bishop method. The reliability is evaluated through the Monte Carlo simulation. Based on the procedure, the effects of different reinforcement parameters and random parameters on the mean safety factor and failure probability of three-dimensional slopes are studied and compared with the results of two-dimensional slopes. Notably, the implementation of an upper sparse and lower dense reinforcement scheme leads to a remarkable enhancement in slope reliability, resulting in a substantial 38.4% reduction in failure probability and a 2.4% increase in the safety factor. Additionally, an effective means of enhancing slope reliability is found to be the increase in the length and number of reinforcement layers. The reliability of 3D reinforced slopes is notably influenced by the spatial variability of soil strength parameters. The degree of influence of autocorrelation distance on the failure probability is ranked as l z  >  l x  >  l y . When l z increases from 1 to 5 m, the failure probability is increased by 221.85%, from 5.4 to 17.38%. As the correlation coefficient is increased from −0.7 to −0.3, the failure probability increased by 26.7%, from 23.2% to 29.4%. The comparison with 2D reinforced slopes reveals that 3D reinforced slopes demonstrate a higher safety factor and a lower failure probability. As a result, slope reliability is tended to be underestimated by the 2D slope analysis.