Interaction between anti-shear galleries and surrounding rock in the right-bank slope of Dagangshan hydropower station  

作　　者：LI Lian-chong XING Ya-zi LIU Xing-zong MA Ke XU Nu-wen ZHANG Fei 

机构地区：[1]School of Resources and Civil Engineering, Northeastern University [2]School of Civil Engineering, Dalian University of Technology [3]College of Water Resources and Hydropower, Sichuan University

出　　处：《Journal of Mountain Science》2017年第7期1428-1444,共17页山地科学学报（英文）

基　　金：jointly supported by grants from the National Key Research and Development Program(Grant No.2016YFC0801607,2016YFC0801602);the National Natural Science Foundation of China(Grant No.51279024);the National Basic Research Program of China(Grant No.2014CB047103)

摘　　要：The fight-bank slope of the Dagangshan hydropower station located in Southwest China is a highly unloaded rock slope. Moreover, large-scale natural faults were detected in the slope body; some excavation-induced unloading fractures were discovered at elevations between lo75m and 1146m. Because of poor tectonic stability, the excavation work was suspended in September 2009, and six large- scale anti-shear galleries were employed to replace the weak zone in the slope body to reinforce the fight- bank slope. In this study, based on microseismic- monitoring technology and a numerical-simulation method, the stabilities of the slope with and without the reinforcement are analysed. An in-situ microseismic-monitofing system is used to obtain quantitative information about the damage location, extent, energy, and magnitude of the rocks. Thus, any potential sliding block in the fight-bank slope can be identified. By incorporating the numerical results along with the microseismic-monitoring data, the stress concentration is found to largely occur aroundthe anti-shear galleries, and the seismic deformation near the anti-shear galleries is apparent, particularly at elevations of 121o, 118o, 115o, and 112om. To understand the interaction mechanism between the anti-shear gallery and the surrounding rock, a 2D simulation of the potential damage process occurring in an anti-shear gallery is performed. The numerical simulation helps in obtaining additional information about the stress distribution and failure-induced stress re-distribution in the vicinity of the anti-shear galleries that cannot be directly observed in the field. Finally, the potential sliding surface of the right-bank slope is numerically obtained, which generally agrees with the spatial distribution of the in-situ monitored microseismic events. The safety factor of the slope reinforced with the anti-shear gallery increases by approximately 36.2%. Both the numerical results and microseismic data show that the anti-shear galleries have a good reinforcement effect.

关 键 词：Slope stability Microseismic monitoring Numerical simulation Safety factor Anti-sheargallery 

分 类 号：TV223[水利工程—水工结构工程]