Study On Leakage Law And Seepage Control Optimization Of Wuluo Reservoir

Earth-rock dam is one of the most common dam types of dams built in China.Reservoir leakage caused by engineering geological conditions and dam materials is a common engineering geological problem.It is usually caused by inadequate anti-seepage capacity of the dam body’s impervious barrier,and the development of fault joints and cracks in the dam foundation.Taking the Wuluo Reservoir in Gongyi City as an example,the numerical simulation method is used to calculate and analyze the seepage law and seepage control of the reservoir,optimizes the seepage control measures,proposes leakage treatment plans for typical earth-rock dams,provides technical guidance for reservoir reinforcement and safe operation of the project,and provides reference for anti-seepage projects of earth-rock dams under similar engineering conditions.Based on engineering geology,hydrogeology,and structural conditions,this article constructs a three-dimensional regional seepage model and a two-dimensional seepage numerical calculation model for typical dam profiles in the research area,and reasonably determines the boundary conditions of the seepage calculation model.Through the inversion calculation of the seepage field in the research area under current conditions,the numerical calculation model is continuously iteratively revised to ensure the rationality and accuracy of the calculation model and parameters.Analyze,evaluate,and optimize the anti-seepage effects of different seepage control measures,in order to propose an economic,reasonable,and effective seepage control plan.The main research conclusions are as follows:(1)The dam foundation of Wuluo Reservoir is a strong permeable foundation.The geological survey of the reservoir engineering and relevant data from indoor and outdoor field tests indicate that there are two large-scale faults developed in the dam site area.One of the faults passes through the dam body and leads downstream,which is also the main channel for reservoir leakage.(2)Analysis of seepage field in the dam site area of Wuluo Reservoir under current anti-seepage conditions.Compared with the absence of anti-seepage measures,the current anti-seepage measures have reduced the leakage amount of the reservoir,but the leakage amount of the reservoir exceeds the capacity of the benefit reservoir by 5.00%,and the current anti-seepage measures cannot meet the anti-seepage requirements;The overall flow trend of groundwater is from southeast to northwest;The groundwater level around the reservoir area is significantly lower than the reservoir water level,indicating that the groundwater in the reservoir area is leaking to the surrounding area.(3)Based on the seepage analysis results of the reservoir current situation,curtain grouting is adopted for seepage control of the main dam and the auxiliary dam at the same time.The bottom line of seepage control depth of curtain grouting for the main dam is 10m below the5Lu line,and that for the auxiliary dam is 5m below the 5Lu line.The results show that the total leakage accounts for 4.87%of benefit storage capacity under normal water level and 6.36%under design flood level.Change the depth of curtain grouting.In Scheme 1,the bottom line of curtain grouting seepage prevention depth of main dam and auxiliary dam is 5m below 5Lu line.The calculation results show that the overall leakage is 5.00%greater than benefit storage capacity under normal water level.In the second scheme,the bottom line of curtain grouting seepage prevention depth of the main dam is reduced to 5Lu,and the auxiliary dam remains unchanged.Under the condition of normal water level,the leakage of this scheme is greater than 5.00%of benefit storage capacity.(4)By taking anti-seepage measures simultaneously on the main and auxiliary dams,the seepage flow rate decreased from 1549.1m~3/d when only anti-seepage measures were taken on the main dam to 968.6m3/d,and the downstream water head of the auxiliary dam decreased from 210.5m to 203.4m;Reduce the bottom boundary of the main dam curtain grouting anti-seepage depth from 5Lu to 10m below the 5Lu line,reducing the leakage amount in the dam site area by 26.28%,meeting the overall anti-seepage requirements and avoiding seepage damage.