三峡库区箭穿洞危岩体变形破坏模式与防治效果分析

本文以三峡库区箭穿洞危岩体为例，对涉水厚层危岩体的变形破坏模式和防护措施进行了研究。根据现场调查和长期监测数据可知，干湿循环作用下基座岩体的劣化是加速箭穿洞危岩体变形破坏的主导因素，并判定其破坏模式为基座滑移式崩塌。在此基础上，将危岩体的防护治理定为两部分，分别是基座软弱岩体的补强加固，以及中上部危岩体的锚索加固。通过数值模拟对防护前后危岩体的位移场以及应力场进行了分析，结果表明危岩体上部的锚索加固能够有效控制岩体的变形，基座补强能够有效控制危岩体的最大剪应力，综合防护可以显著提高箭穿洞危岩体的稳定性。该防护措施的理念及方法，可以为库区涉水危岩体的治理提供重要的参考价值。

Analyses on failure modes and effectiveness of the prevention measures of Jianchuandong dangerous rock mass in the Three Gorges Reservoir area

In this paper, the Jianchuandong dangerous rock mass in the Three Gorges Reservoir area is taken as an example to study the failure mode and protection of submerged thick-layer dangerous rock mass. Based on field investigation and the monitoring data, it was found that the degradation of the base rock mass under the dry-wet cycles is the main factor to accelerate the deformation of the dangerous rock mass. Its failure mode is determined as slip collapse. According to the deformation and failure characteristics of the dangerous rock mass, the corresponding treatment measure is divided into two parts, inculding the reinforcement of the weak base rock mass, and anchor cable in the upper part of the dangerous rock mass. By comparing the displacement field and the stress field before and after protection, it is found that the prestressed reinforcement of the upper dangerous rock mass can effectively control the deformation of the rock mass, and the reinforcement of base rock mass can effectively control the maximum shear stress of the dangerous rock mass. The comprehensive protection effect is significant to ensure the stability of dangerous rock mass. The protection method can provide important reference for the treatment of submerged dangerous rock mass in the reservoir area.