江垭电站地下厂房洞室围岩监测与分析

为监测江垭水利枢纽地下厂房洞室围岩的稳定性 ,在地下厂房的 3大洞室共布置了 4个观测断面并埋设各类测试计 478支 ,随着洞室开挖过程进行监测设施埋设施工和观测。监测成果反映了施工期洞室围岩的位移变化、应力分布状态 ,经与有限元计算成果比较 ,其位移变化、应力分布规律一致。洞室局部曾出现过几条裂缝 ,通过对裂缝观测成果及成因分析 ,已进行了处理。根据对地下厂房洞室围岩监测与分析 ,对洞群围岩稳定性的初步评价是 :厂区岩体较坚硬完整 ,锚喷支护后的围岩变形较小 ,锚杆应力值不大 ,几条洞室局部曾出现的裂缝经过处理 ,已不再发展。因此施工期间地下厂房洞群围岩整体稳定性较好 更多还原

Monitoring and analysis of surrounding rock mass of underground powerhouse chambers of Jiangya Power Station

In order to monitor the stability of surrounding rock mass of underground powerhouse of Jiangya project,4 observation sections were arranged for 3 large underground chambers and 478 observation instruments were embedded.The observation was carried out in the process of chamber excavation. The monitored data demonstrate that the displacement variation and stress distribution of the surrounding rockmass during the construction period conform with FEM computed results.Several fissures occurring in local area of the chambers had been treated after analysing the observation results and genesis of the fissures.Through monitoring and analysis the preliminary evaluation concludes that the rockmass in the area of powerhouse is intact solid,the displacement of the anchorage and gunite supported surrounding rock is small,the stress of anchor rod is also small.The fissures occurring in some local area of chambers have stopped further development after being treated,so the surrounding rockmass of underground powerhouse chambers is stable integrally.