Failure of a Rock Slope Ten Years after Excavation
Keywords:High artificial rock slope, Time since excavation, Failure, Weathering, Geological structures.
In the present study, a rock cut slope in Chongqing of China, which failed suddenly about ten years after excavation, was reported. The survey results after failure indicated that the rock masses of the rock slope were highly fractured and heavily weathered, the critical slip surface was composed of three connected discontinuities from the toe to top of slope. The factors resulting in the failure of rock slope were mainly initial excavation and weathering process. The initial excavation removed original supporting role of the excavated rock masses at the toe of the slope to the upper unexcavated rock masses, and broken the original ground stress balance. The physical and chemical weathering after the initial excavation cracked progressively the rock masses, deteriorated the mechanic properties of the rock masses, and changed the stresses and strains in the rock slope. The stability of high artificial rock slope during operation should be paid attention to. The characteristics of geological structure, unloading induced by excavation, and weathering have important effects on the evolution for deformation of artificial rock high slope.
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