堆石体流变对分期浇筑的面板变形影响研究

STUDY OF INFLUENCE OF ROCKFILL RHEOLOGY ON FACE DEFORMATION WITH SUBSTAGE CONSTRUCTION

采用高围压下的幂函数流变本构模型对水布垭面板堆石坝进行考虑堆石流变的应力、变形分析,其结果表明,考虑堆石流变后的坝体沉降和面板变形有明显的增加。由于堆石体流变变形的影响,对于分期填筑高混凝土面板坝,各期面板的浇筑时间与其下卧的堆石体临时断面填筑时间存在一个最短的时间间隔,在给定面板浇筑时间条件下,面板的最大浇筑高程与其下卧的堆石体临时断面顶部之间应保持一最小高差,以防止面板与堆石体产生不协调变形,导致面板顶部与下卧的堆石体之间出现脱空现象。因此,必须根据面板坝的流变分析成果对堆石体填筑过程和面板浇筑过程进行优化,以减小面板的应力、变形。

Based on a rockfill power function rheology constitutive model, the stress and deformation analysis with the consideration of rockfill rheology are performed for Shuibuya concrete face rockfill dam（CFRD）. The computational results show that the deformation of dam shows evident increment and the rheology has an obvious influence on the deformation and stress of the face. Due to influence of rockfill rheology, the shortest time interval exists between construction periods of concrete faces lying on the rockflll and the rockfill. At the same time, the minimum elevation difference should also be satisfied between construction elevation of concrete faces lying on the rockfill and the rockfill top, in order to avoid inconsistent deformation between concrete faces and the rockfill. So it is very important that construction processes of rockfill and concrete face must be optimized and deformation of face should be reduced as possible.