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| Simulation of seepage problems in unsaturated soil using the smoothed particle hydrodynamics(SPH) method |
| CHEN Peipei，BAI Bing |
| (School of Civil Engineering，Beijing Jiaotong University，Beijing 100044，China) |
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Abstract The unsaturated soil seepage occurs widely in the dam seepage，rainfall infiltration and pollutants diffusion in landfill etc. The numerical solution of unsaturated seepage equation of Richards based on the finite element algorithm has been derived with the matrix suction head as the independent variable. However，the strong nonlinear characteristics of the material properties leads to the poor mass conservation properties and non physical oscillation of the numerical solution，and may cause inconvergence of the iterative process at the same time. In order to obtain a numerical solution with mass conservation，smoothed particle method was introduced into the solution of the head-based form of Richards equation，and the practicability and reliability of the new algorithm was verified by a numerical example. Finally，a complex unsaturated seepage problem with the evaporation condition was simulated using a program which was written based on SPH algorithm.
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2016, Vol. 35 
