Research On Slope Characters And Deformation Tendency Of Jinchang Dam In Guandi Hydropower Station On Yalongjiang River

In February 2012, ground deformation was found around the Jinchang Dam of Guandi Hydropower Station. In order to have the plant operating safely and on time, as well as protect local lives, properties and the Guandi Hydropower Station itself, it is vital to study the deformed terrene’s characters, its trend, and proper counter-measures. This paper uses geological exploration and safety monitoring methods to conduct research and analysis on the stability of the deformation located at the right bank 17 km upriver of the Jinchang Dam. Cracks, shifts(deep shifts included), precipitation, ground water level are monitored accordingly around the Jinchang Dam of Guangdi Hydropower Station. Considering the potential hazards do exist if sending a monitoring staff, in order to obtain data in real time, some of the shifting points were monitored by GPS.Based on the observation and monitoring results, as well as applicable analysis done on other ground deformation, it is very unlikely that the ground deformation at Jinchang Dam will lose its stability. If the ground deformation disintegrates progressively, though it may have little impact on Guandi Hydropower Station, it will have certain impact on local people, buildings under the affected height; and it may potentially influence the shipping safety in the reservoir area.he thesisdiscussed and studied the system monitoring at Jinchang Dam of Guandi, the finding through the study on the monitoring is as below:(1)The deformation out the sliding area of the dam is weak。No obvious land subsidence or sliding was found on the land surface out of the dam sliding area,also no distribution of the tension crack was found.(2)The deformation is obvious on sliding area I ~ IV, mainly reflected instretching expansion loose of the calcification in front part, the sliding deformation on the upper and middle part, tensile deformation and land subsidence on the downstream. The deformation differs from different parts on sliding area I~IV, which is strongly deforming area.(3)The statistics of the regional deformation rate of different measuring points. The thesis also studied the deformation development trends and forecasts deformation value, analyze the surge hazard that may happened in the different modes of instability, the possibility of the river blocking, and bring up the early warning measures.Through the system studying and analysis, the thesis comes up with 5 conclusions, and brings up 4 suggestions on the measures against the land sliding area of the dam:(1)The overall stability against the sliding in the theJinchang Dam of Guandi is good, and the stability of area IV is very important, it controls the stability of all the other area. The suggestion is to take load shedding + prestressed anchor on the top of slop in area IV.(2)In order to enhance the stability against the sliding, it is very necessary to drain the surface water and decrease the underground water level decrease.(3)Give necessary cut to the back part of area III.(4)Suggest to take the engineering monitoring as the mainly measure, together with surface drainage, and other necessary measures according the monitoring findings.