Ramin Ghazanfari - Department of civil engineering, Kharazmi University, Tehran, Iran,
M.Saleh Baradaran - Department of Civil Engineering, Islamic Azad University Mashhad Branch, Mashhad, Khorasan Razavi, Iran,

One of the most important major things that have a serious effect on earth dam is the seepage through dams and foundation of them. Some commonly method for controlling this happening is use the cut-off wall. In this study we modeled the cut-off wall with material that are similer to dam’s core. In addition, we change some parameters of cut-of wall such as these angle ratio to the horizontal earth surface axis , depth of cut-off and their location, and the effects of this changes on seepage and piping from dam been investigated. With analysis the result of SEEP/W software, we present some charts that show this result on seepage. On the other part of this paper we try to analysis effect of these parameter’s changes of cut-off wall on some parameters such as liquid velocity and pore water pressure and present some charts about this effects. By the obtained results from SEEP/W (V. 2007) and charts, geometry’s parameter of cut-of walls have affected on seepage and piping in earth dam.

cut-off wall; piping, angle ratio of cut-off; depth of cut-off; pore water pressure