某水电站厂房调压室半确定性块体稳定性浅析

Stability Analysis of Semi-Deterministic Blocks for the Surge Chamber in the Factory Building of a Hydropower Station

半确定性块体是由岩体中的确定性结构面和随机结构面(基体裂隙)组合切割形成的块体,此类块体分布常沿确定性结构面及其交错处呈带状或集中分布,形成的规模可大可小,在工程中未得到足够的重视,但其稳定性至关重要,会对施工安全造成较大影响。以某水电站厂房调压室内可能形成的半确定性块体为例,根据各级结构面性状分析能否构成块体,以及块体形成后的稳定性问题。采用了由成都理工大学地质灾害防治与地质环境保护国家重点实验室以矢量计算法开发而成的SASW程序进行计算,并综合一些经验数据得出较为准确的块体稳定性系数。以此对洞室半确定性块体稳定性进行了初步的研究,为此类施工方案的安全防范提供了一定依据。

Semi-deterministic block in a cavern is composed by the deterministic and random structure surfaces （matrix fracture） in a rock mass. The semi-deterministic blocks usually show zonal or centralized distribution along the deterministic structure surface and the intersections between the deterministic structure surfaces, and their sizes are very random. Little attention has been paid to these blocks;however, the stability of the blocks is crucial to the construction safety. The semi-deterministic blocks in the factory building of a hydropower station are investigated in this paper, including the analysis of the possibility for the formation of the semi-deterministic blocks based on the structure surfaces at all levels and the stability of the blocks once they develop. The SASW program is used to calculate the stability factors of the blocks, and this program is developed by Chengdu University of Technology and based on the vector calculation method. The stability of the semi-deterministic blocks in the cavern has been preliminarily studied, which can be beneficial to the knowledge of the construction safety in these blocks.