面板堆石坝面板竖缝特性对面板应力变形影响分析

Effect of vertical joints on stress-deformation behavior of CFRD

采用三维有限元方法,研究了面板竖缝特性对面板堆石坝中面板应力变形的影响。基于类似子结构法概念,建立了精细模拟面板及其分缝特性的三维有限元分析方法。针对马来西亚巴贡面板堆石坝,计算了多种面板竖缝宽度和填料的方案,得到坝体和面板的应力变形。计算结果表明,面板竖缝几何尺寸和填料特性对面板的挠度、顺坡向应力、水平向压应力和周边缝张合变形影响不大,而对面板的水平向拉应力和竖缝压缩量影响很大;面板竖缝填料变软和宽度增大均会导致面板的水平向压应力减小,而竖缝压缩量明显增大;采用软木作为填充材料较之填充硬木,可以大约降低一半的压应力;面板竖缝宽度及其填料特性对同期填筑的面板、特别是邻近的面板水平向压应力影响较大。

A three-dimensional finite element method was adopted to investigate the behavior of a concrete faced rockfill dam （CFRD） including the thin vertical joints of face slab on the basis of substructure concept. Using this method, we analyzed the stress-deformation behavior of the Bakun CFRD in Malaysia by different filling materials and widths of vertical joints of face slab. The analysis results show that the filling materials and size of the vertical joints have insignificant effect on the deflection, slope-direction stress, horizontal tension stress and peripheral joints＇ deformation of the face slab; but they have a significant effect on the horizontal compression stress of face slab and the compression deformation of vertical joints. By decreasing the modulus of filling material or increasing the width of the vertical joints, the horizontal compression stress can be decreased while the compression deformation of vertical joints can be increased. The horizontal compression stress can be decreased by a half if using softwoods instead off hardwoods. Such an influence may be significant for the same stage face slab, especially for the neighboring one.