川藏铁路折多山隧道进口岩崩运动特征及防治措施

川藏铁路折多山隧道进口沟槽两侧岩屑坡大量发育,岩屑坡失稳破坏形成崩塌滚石灾害,严重威胁铁路安全。通过现场调查、理论分析、数值模拟以及力学分析综合评价洞口岩屑坡的形成因素、运动特征及危害,提出了可行的治理方案。为预测和评估折多山隧道进口上部危岩崩塌体的运动过程及影响,基于三维真实地形,考虑不同位置的岩体崩塌运动,建立了危岩体三维离散元模型,得到了洞顶危岩崩塌体的运动特征以及最危险的岩屑坡整体失稳的运动特征。此外,基于数值模拟的结果,通过理论分析,计算了最不利情况下的崩塌落石路径及冲击能量,得到了隧道洞口的危岩体的影响范围。最后,根据隧道洞口危岩及岩屑坡的分布区域及运动特征,提出了"以防为主,防挡结合"的综合治理方案。

Movement Characteristics and Prevention of Talus Slope In ZheDuoShan Tunnel of Sichuan-Tibet Railway

The talus slope, standing at the entrance of ZheDuoShan tunnel, Sichuan-Tibet Railway, have greatly threatened the security of railway, if it becomes to be the collapse and rock roll. Based on the data from the field observation and the results from the numerical and theoretical analysis, we make a comprehensive analysis on the talus slope, including formation mechanism, movement characteristics and its hazard effect. Hence , To figure out the movement characteristics and the affecting area of the rock falls, we used the 3D Distinct Element Method to create a three-dimensional computing model, which are based on the real environment of ZheDuoShan, of the dangerous rocks, located in different sections Finally we obtained the moving path of the dangerous rocks as well as the most dangerous talus slope, which stands at the top of the mountain, On the other hand, based on the results of the numerical analysis, theoretical calculation of the dangerous rock falls, focusing on the compact energy and the moving path have been made to assess the risk of the most dangerous talus slope. In a word, we can get the affecting area of the dangerous talus slope by using the numerical and theoretical analysis. Finally, based on the above results, mainly including the moving path and the affecting area, we suggested that manage the talus slope must prevent it and combined block.