GEOPHYSICAL APPRAISAL AND ANALYSIS OF GROUTING EFFECTS IN THE TIAHSHENQIAO SECOND-GRADE CASCADE HYDROPOWER STATION
YUAN Jing-hua1,2, XIAO Hai-yun3
1. China University of Geosciences, Wuhan 430074, China;
2. Guiyang hydroelectric Investigation Design & Research Institute of the State Power Corporation of China, Guiyang 550002, China;
3. Hunan Geological Survey Research institute, Xiangtan 411100, China.
The Tianshenqiao second-grade cascade hydropower station is a diversion-type power station. Because of the existence of relatively long diversion tunnel crossing complicated strata, karst and structures, conceptual schemes of reinforced liner and pile foundation were adopted to tackle the harmful geologic hole section. Besides, the surrounding rock underwent high pressure consolidation grouting to strengthen its stabilities. The quality of grouting was checked by water-pressure test and integrated geophysical prospecting. This paper mainly describes the unique designing thought in geophysical test, data processing, and methods, results and analysis of grouting effect appraisal in three diversion tunnels, in which the special section of main holes Ⅱ,Ⅲ and harmful geologic bodies were treated according to the corresponding design schemes.