Study On Seepage Analysis Of Concrete Face Rockfill Dam Of Yangjiang Yangqi Hydropower Station

Concrete face rockfill dam dam seepage stability calculation,usually don't do because of the high dam project belongs to the level of concrete face rockfill dam,dam layer thickness is larger,the dam site geography weather,all of these will make concrete face is in bad condition,to provide reliable basis for design and construction,ensure the safety of the dam dam reasonable arrangement and engineering seepage analysis and calculation,it is necessary to simulate analysis of dam body seepage characteristics.This paper will take the dam as the main research object,the seepage calculation and analysis of main dam equipotential surface,pressure head,pore water pressure,saturation line and infiltration surface seepage elements distribution,etc.Verify the dam in various areas and seepage stability of dam foundation layer,demonstrate the reliability and safety of face rockfill dam and provide reference for the similar design of the dam.In this paper,starting from the basic theory of percolation,the paper analyzes the three dimensional seepage calculation of random variational principle and the stochastic finite element formulations,this paper expounds the principle and steps of the finite element method for solving seepage problem,through the introduction of the basic principle of seepage analysis of the finite element method and the general calculation steps,according to the characteristics of seepage field,by using large-scale finite element analysis software Midas GTS,face rockfill dam for 2d and 3d seepage problem solving,with its unique solution seepage element to determine within the dam body seepage head position and each point of water pressure on the dam body and its results intuitive and accurate and are presented in the form color cloud picture or list.Under steady state,the head of dam in wear and tear is mainly within the dam,the upstream dam surface of concrete face water retaining ability is good,steady state solution for unsteady seepage calculation provide an initial state.Through the qualitative analysis of unsteady seepage of the concrete face rockfill dam,when upstream water level declines at the rate of 1m/d,the dam water level drop 5days of water head and water pressure,and gives a stable water levels fall within 2days after water head and water pressure,it can be seen that total water level changes in the dam body position only occurs in the upstream of dam area,precipitation within 5days as the upstream water level drops,dam head also reduced,5days later stabilise water levels fall,head of basic remain unchanged.When upstream water level is lower,the overflow of the pore water pressure in the dam body is zero surface also with lower water level is reduced,and as the growth of the time in the upstream of dam seepage is more stable,the seepage influence area bigger,pore water pressure area with the enlargement of the seepage area and also bigger.When upstreamprecipitation stability,dam body seepage water level change is not obvious,and pore water pressure change is not obvious.Example results show that by using finite element analysis software Midas/GTS seepage module is feasible for seepage analysis of the concrete face rockfill dam,this for our future in CFRD dam seepage analysis and the research provides a new research ideas and methods,has a certain reference value.