Mechanism Analysis of the Failure for a Safe Jointed Rock High Slope: Tectonic Structures and Damage

Abstract

Tectonic structures and tectonic damage of rock slope have an important effect on its failure mode, but it isn’t always paid attentions in actual engineering works. In the present study, a rock cut slope in Chongqing of China was reported. The survey results during the construction of the expressway indicated it should be safe, but it failed at last. The main reason is that tectonic tectonics and tectonic damage are not adequately taken into account in the design of this slope. The strong folds make the slope rock mass broken. Three groups of joints in the rock masses of the rock slope provide geometric conditions for landslides, and the further possible failure of the rock cut slope may follow the three group joints. The excavation change the stress environment of the slope and promote the destruction of the slope. Due to weathering processes, the integrality and shearing strength of the rock masses were reduced. The time-effect of excavations and weathering-effect are interacting with each other. Eventually, the slope not only slipped along the structural surface, but also produced plastic deformation damage. This indicates that in the design of the slope, the tectonic structures and tectonic damage must be fully considered, time effect is a factor which cannot be ignored.