Stability of expansive soil slopes reinforced with anchor cables based on rotational-translational mechanisms

Abstract

Expansive soil slopes are usually characterized with conspicuous fissures. Pre-stressed anchor cables are effective techniques in improving the slope stability. Explicit considerations of the fissures and the suction effect become crucial in producing more realistic solutions. Based on the kinematic limit analysis theorem, this paper performs a limit analysis of the stability for expansive soil slopes stabilized by anchor cables. The upper bound solution to the slope stability was optimized and compared with the published solutions, demonstrating the applicability of the proposed method. An illustrative slope reinforced with two different reinforcement patterns was investigated to show the role of soil suction and anchor reinforcement in the safety assessments of expansive soil slopes. The results indicate that the slope stability and anchor reinforcement relate closely to the fissures. A threshold value of the fissure height exists, beyond which the slope stability is significantly reduced. An optimum inclination angle (ξopt) of anchors exists universally and is reduced as the anchor height, the internal friction angle and the surcharge load increase.