【摘要】 用两种材料的离心模型研究边坡倾倒破坏机理。石膏材料做的试验说明，数值模型不仅能模拟块状岩体的倾倒过程，而且能合理地考虑锚索的作用；人工石材料作的试验发现，运用数值模型分析离心模型试验时，只有考虑裂缝对材料的影响以及对岩体抗拉强度进行等效修正，两者才能获得一致结果。此外，试验还证实了破坏面是一个在坡趾处位置较深的双折线型滑面更多还原

【Abstract】 This paper presents the results of the centrifuge model testing for the investigation of the mechanism of slope toppling failure. The tests consist of two steps. In step 1, the rectangular gypsum columns failed at an acceleration of 78 g , presenting a failure model that had 3 stable blocks at the crown, 9 toppling blocks in the middle and one sliding block at the toe. The numerical model proposed in a separate paper(Chen, et al, 1996)predicted a critical acceleration of -0 58×10 -3 g , a magnitude close to zero provided that the shear strength parameters employed is based on Lajtai′s theory(1969). Another model with an anchor at the 8th block produced similar failure mode at an acceleration of 108 g . The numerical model gave a critical acceleration of 7 08×10 -3 g , very close to zero again. In step 2, the cement block with iron powder and sand mixture allowed the model to have similar unit weight and mechanical properties to those of rock. A joint set dipping outside the slope was simulated by cutting the block with a manual saw. The model failed at 130 g . Cracks developed in the intact concrete bridges. It was found that numerical approaches could not predict the acceleration at failure unless the tensile strength of the concrete was reduced from the original 4 81MPa to 1 58MPa,based on the theory of fracture mechanics. In so doing, the numerical method gave a factor of safety of 0 953.更多还原