The Numerical Analysis Of Seepage And Stability On Saturated-unsaturated Earth Rock-fill Dam

The earth rock-fill dam is an important dam type and widespread in the field of hydraulic engineering.It has the advantages of simple structure and convenient construction.There have been tens of thousands of earth rock-fill dam in the world currently.The analysis and evaluation of its safety is particularly important.Seepage problem is accounted for a large proportion in the factors affecting the security and stability of earth rock-fill dam. Coupled with the special circumstances of China’s hydraulic engineering development,it is of great significance to the study on seepage and stability of earth rock-fill dam.Numerical analysis on seepage and stability has been widely used with the rapid development of computer. Seepage and stability are analyzed by HydroInfo hydraulic system and GeoStudio software’s SEEP/W, SLOPE/W module combined with the Xiangshui water conservancy project.The saturation line.seepage field distribution and the security and stability value of the upstream and downstream slope are achieved in the conditions of the normal storage water level and flood water level,whose core wall are normal and failure.The two results are consistent.The results show that core wall plays an important role in dam anti-seepage. The dam’s saturation line is elevated after the failure of core wall. It is very unfavorable to the stability of the slope.The slope stability analysis shows that the upstream slope does not meet the requirements of the design specifications. The corresponding measures should be taken to reinforce the slope.Unsaturated soil is often encountered in Engineering.Because unsaturated soil exists negative pore water pressure.the permeability function and volume water content function need to be considered in the permeation properties of unsaturated soils.The transverse section of clay core rock-debris dam of Xiangshui hydraulic complex engineering is selected as the research object.The method of coupling analysis of GeoStudio is used to analyze the unsaturated seepage field -stress field and calculate the factor of safety against sliding in the clay core rock-debris dam.By this coupling analysis,heads of unsaturated seepage field and the value of safety factor against sliding are resolved.The horizontal and vertical displacement are showed with time. It shows that the slope displacement changes slowly in the deep zone and changes of displacement in the shallow slope is relatively large by comparing with the stress field and the seepage field in the non-coupling analysis condition.It also shows that stability of the upstream slope base is not enough by comparing with the stability of the slope in the non-coupling analysis condition.The methods of gentle slope or paving stone and pressing slope should be adopted to improve the stability of the slope.Then it explains that the coupling analysis has more practical significance.