坝踵混凝土体型对混凝土面板应力变形的影响

Influence of concrete heel shape on stress and deformation of concrete slab of a dam

镶嵌混凝土面板堆石坝是一种可以改善高面板堆石坝应力变形的新坝型。利用平面有限元法分析计算不同坝踵混凝土结构高度、下游坡比、趾板位置时面板的应力变形和周边缝变位,进而探究镶嵌混凝土面板堆石坝中坝踵混凝土结构对面板应力变形的影响。结果表明:当坝踵混凝土结构高度从坝高的27%增加到坝高的40%时,面板的挠度和顺坡向应力都大幅减小;坝踵混凝土结构的下游坡比从1∶0. 4放缓到1∶0. 7时,面板应力变形变化幅度较小;趾板位置在坝踵混凝土顶部从下游向上游移动时,面板与趾板之间的周边缝张开变位和错动变位大幅减小了68. 7%和85. 8%。说明设置坝踵混凝土结构可有效改善面板的应力变形。

The embedded concrete composite dam is a new type of dam which can improve the stress and deformation conditions of a high concrete face rockfill dam.Further analysis of the influence of the concrete structure of the heel of the dam on the stress and deformation of the embedded concrete composite dam has been investigated in this paper,based on analyses of the stress deformation of the concrete slabs and the displacement of the peripheral joints of different heights and the downstream slope ratio and the different positions of the plinth.The results have shown that when the height of the concrete structure of the heel of the dam was increased from 0.27 times to 0.4 times the height of the dam,the deflection and the stress along the slope of the face slab were greatly reduced,and that when the downstream slope ratio of the concrete structure of the heel of the dam was reduced from 1∶0.4 to 1∶0.7,the variation in the stress and deformation of the face slab was relatively small.When the position of the toe plate was changed from downstream to upstream at the top of the concrete heel of the dam,the opening displacement and dislocation displacement of the peripheral joint between the face slab and the toe slab decreased significantly by 68.7% and 85.8% respectively.The results show that the stress and deformation of the face slab could be effectively improved by setting the concrete structure of the heel of the dam.