Modified Bishop method for stability analysis of weakly sloped subgrade under centrifuge model test

• Published in: Frontiers of Structural and Civil Engineering 2021-06, Vol.15 (3), p.727-741
• Main Authors: Sheng, Ke, Hong, Bao-Ning, Liu, Xin, Shan, Hao
• Format: Article
• Language: English
• Subjects: Accuracy; Centrifuge model; Cities; Civil Engineering; Countries; Design modifications; Engineering; Inclination angle; Mathematical models; Model testing; Potential energy; Regions; Research Article; Safety; Safety factors; Slice method; Sliding; Slope stability; Stability analysis
• ISSN: 2095-2430; 2095-2449
• DOI: 10.1007/s11709-021-0730-z

The sliding forms of weak sloped and horizontal subgrades during the sliding process differ. In addition, the sliding form of weakly sloped subgrades exhibits considerable slippage and asymmetry. The accuracy of traditional slice methods for computing the stability safety factor of weakly sloped subgrades is insufficient for a subgrade design. In this study, a novel modified Bishop method was developed to improve the accuracy of the stability safety factor for different inclination angles. The instability mechanism of the weakly sloped subgrade was considered in the proposed method using the “influential force” and “additional force” concepts. The “additional force” reflected the weight effect of the embankment fill, whereas the “influential force” reflected the effect of the potential energy difference. Numerical simulations and experimental tests were conducted to evaluate the advantages of the proposed modified Bishop method. Compared with the traditional slice method, the error between the proposed method and the exact value is less than 32.3% in calculating the safety factor.