Shen Zhenzhong

Penalty Function Element-Free Method for Solving Seepage Problem of Complex Earth Dam

The element-free method (EFM) simplifies the pre-processing and has high calculation efficiency since it requires only the information of nodes and boundaries instead of elements. By taking the adaptive influential radius and arranging nodes flexibly, homogenization could be reduced significantly. Such method was applied in this paper to calculate the steady seepage field of a core wall dam with anti-seepage curtain and concrete cushion. The comparison of the calculation results with that calculated by the finite element method shows they match well and both the seepage field and free surface distribution accord with the general rules, which mean the element-free method can be applied to solve the seepage problem of complex earth dam.

Dynamic characteristics analysis and seismic safety evalution for Madushan Gravity Dam

According to the engineering geological condition of Madushan RCC Gravity Dam, the 3-D finite element model of the joint effect of the dam and its foundation is established to analyze dynamic characteristics and evaluate seismic safety of Madushan dam. In this paper, dynamic time history analysis method is applied to calculate the dynamic response of the roller compacted concrete gravity dam so as to obtain the seismic acceleration response, displacement and stress response and their distribution. The foundation stability against sliding is analyzed by the point safety factor method and the strength reserve safety factor method. The calculation shows that, in VII seismic fortification intensity, the maximum displacement response of the dam is 13.18mm, the maximum stress response is 2.264MPa, the maximum acceleration response is 3.628m/s2, magnification of 3.69, thus the strength of dam meets with the requirements. Meanwhile the foundation point safety factors of the overflow dam are all greater than 1, no continuous foundation failure surface, and the dams strength reserve coefficient is 3.68. So the dam meets with the safety requirements.