川藏高速公路汶(川)马(尔康)段崩塌危岩发生机制与防治

Mechanism and Prevention of Collapse Dangerous Rock in Wen(chuan) Ma(Er Kang) Section of Sichuan Tibet Expressway

川藏高速公路建设以来发生了上百处崩塌灾害,对工程建设形成了极大的危害。通过选取5处特征各异、处治措施不同的崩塌危岩边坡实例,经地质分析,对崩塌的发生机制与工程防治进行研究。研究结果表明:川藏高速公路崩塌危岩的形成机制与有利的地形地貌、岩土体类型,活跃的地质构造活动,恶劣的气象水文条件和高强度的人类活动等有着密切的关系;崩塌多发生于突出山脊的前缘,依据地质条件和变形破坏演变过程,其典型地质力学模式包括:倾倒式、滑移式、坠落式和滚落式四种;崩塌处治方案的确定应针对性的依据病害体的地质条件、工程的安全性和经济性,以及处治工期等进行综合确定。

Hundreds of collapse disasters have occurred since the construction of Sichuan-Tibet expressway,which have caused great harm to the project.Five examples of collapse dangerous rock slopes with different characteristics and treatment measures are selected in this paper.Through geological analysis,the occurrence mechanism of collapse and engineering prevention and control are analyzed.The results show that:(1)the collapse of Sichuan-Tibet expressway is closely related to favorable topography and landform,rock and soil types,active geological tectonic activities,bad meteorological and hydrological conditions and high-intensity human activities;(2)collapse occurs mostly in the leading edge of the protruding ridge,according to geological conditions and evolution process of deformation and failure.The typical geo-mechanical models include four types:toppling,sliding,falling and rolling;(3)the determination of collapse treatment scheme should be based on the geological conditions,the safety and economy of the project,and the treatment period.