Numerical Application Of Saturated - Unsaturated Seepage Theory In Low Permeability Medium Of Dam

Phenomena of seepage were exist in various fields of engineering. It was proved that many accidents are caused by seepage, so the prediction and analysis of seepage field of great significance. The main contents of this paper include the following aspects:(1) Many previous studies have ignored the impact of non-saturated soil matric suction of seepage, leading to the calculation results and the actual existence of a certain bias. To make the simulation results more accurate, both saturated zone and unsaturated zone as one unit were put into consideration. The saturated and unsaturated seepage model were established based on Darcy’s law. Two variables including piezometric tube waterhead and saturation were used for study seepage field. The saturation line of seepage field can be captured by distribution of saturation.(2) The calculation program of saturated and unsaturated seepage were designed using FORTRAN language. Entity modeling were established according to the study work by mean of using ANSYS software. Input informations of elements and nodes then the pre-processing program could calculate and output elements topological relations. The main program processing the remain work and output results by mean of TECPLOT software.(3) According to the results of previous studies of others, two typical examples of procedures were adopted to verify the accuracy of the program.(4)Take three dams which has been built recently as example, use the program designed calculate the numerical models of seepage in low permeability media, then analysis the results. All this work is aim at predicting seepage field and provide informations for engineers which can be used for project seepage controlling.Results of this study is that the saturation zone and unsaturated zone were put into consideration as one unit. Saturated and unsaturated flow model were established. The program was designed by FORTRAN computer language, both pre-treatment and post-processing module were optimized. It was approved that the program can be used for calculate seepage field of dam with low permeability media.