The present study investigates the effects of clay core thickness and cutoff wall depth on some of the design parameters in the Sabalan rock fill dam by the finite-element method using the SEEP/W software. Clay cores with various thicknesses and cutoff walls in different situations of dam foundations were tested. The results revealed that (1) the maximum hydraulic gradient in Sabalan dam foundation occurs in the cutoff wall; (2) the minimum hydraulic gradient can be found by changing the location of the cutoff wall, under the center of clay core; and (3) discharge reduction depends on the optimum position at heel of the core. As the permeability decreases and the depth of the cutoff wall increases, the hydraulic gradient in the cutoff wall increases. As the thickness of the clay core increases, hydraulic gradient and the seepage discharge decreases and the uplift pressure increases.

中文翻译：

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萨巴兰大坝的上升压力和水力梯度

本研究使用SEEP / W软件通过有限元方法研究了萨巴兰堆石坝中粘土芯厚度和防渗墙深度对某些设计参数的影响。在不同的坝基情况下，测试了具有不同厚度的粘土芯和防渗墙。结果表明：（1）萨巴兰坝基最大水力梯度出现在防渗墙中；（2）在黏土心的中心下方，通过改变防渗墙的位置可以找到最小水力梯度；（3）放电减少取决于铁心根部的最佳位置。随着渗透率的降低和防渗墙深度的增加，防渗墙中的水力梯度会增加。随着粘土芯厚度的增加，