大型地下厂房施工期围岩变形监测成果分析

地下工程监测是工程动态设计和信息化施工的重要基础，监测成果全面、准确、及时的总结和分析上报更是其中重要的环节。乌江彭水电站地下厂房开挖尺寸大、地质条件复杂、开挖周期长、施工扰动大，为保证施工期和运行期的安全，在地下厂房区布置了大量的监测仪器，对厂房施工期围岩的变形性态与稳定性实施跟踪监测。通过监测成果分析表明：主厂房围岩总体上是稳定的，设计支护措施可以提高围岩的自稳能力，保障厂房开挖的稳定。但是受地质条件和爆破施工影响，局部围岩特别是下游边墙页岩部位岩体稳定性问题突出。

Analysis of deformation monitoring of large-scale underground powerhouse during construction period

Monitoring is one of the important bases for dynamic design and information construction in underground project, and the analysis and reporting of monitoring information are even more important, if they are all-sided, accuracy and timely. The excavation of underground powerhouse of Pengshui project in Wujiang River faces many problems, such as large-scale span and height, complex geological conditions, long period, the disturbance of construction, etc. In order to ensure safety of construction and operation, many monitoring instruments were installed in underground powerhouse, which were used to monitor the deformation and stability of surrounding rockmass in construction. The analysis of monitoring results indicate: the surrounding rockmass of underground powerhouse is stable in general; design supports can enhance the self-stability of rockmass and ensure the stability of underground powerhouse; however, the stability of some local rock masses, especially the shale in the downstream sidewall are bad due to geological condition and rockmass blasting.