椭圆-抛物线双屈服面流变模型的应用与研究  

Creep model using oblong-parabola double-yield surface and its application

作　　者：王海俊[1] 董卫军 田志军[1] 常青 WANG Haijun DONG Weijun TIAN Zhijun CHANG Qing(Jiangsu Province Water Conservation Survey Design and Research Institute Co.Ltd ,Yangzhou, Jiangsu 225127 Eastern Route of South-to-North Water Diversion Shandong Main Line Co.Ltd, Jinan 250013)

机构地区：[1]江苏省水利勘测设计研究院有限公司,江苏扬州225127 [2]南水北调东线山东干线有限责任公司,济南250013

出　　处：《水力发电学报》2017年第1期96-103,共8页Journal of Hydroelectric Engineering

摘　　要：堆石料具有剪胀、剪缩和流变等特性,堆石料流变严重影响高土石坝心墙、面板等结构的受力变形。为此结合室内试验,建立了一个考虑堆石流变特性的双屈服面流变模型。本文以水布垭面板堆石坝为例,采用双屈服面流变模型对坝体沉降变形、面板应力和挠度进行分析。计算结果表明:该模型能够综合反映复杂加载情况下堆石料剪胀、剪缩和流变特性;流变对坝体及面板的应力变形呈增大效应;200 m以上的高坝满蓄后5年左右流变效应仍未完全趋于衰减稳定;流变对面板拉应力的影响较大,轴向拉应力增幅达30%,顺坡向则次之;对比现场观测资料,自然界日晒雨淋过程会对堆石长期变形产生影响,现有的流变计算中均忽略了此类因素的影响,导致计算结果小于实测结果。Rockfill material is featured with dilatation, shrinkage and creep; and its creep can seriously affect stress and deformation in the core wall and concrete face slabs of a high dam. By conducting creep tests on different rockfill materials, we have developed a double-yield surface creep model that can simulate visco-elasto-plastic behaviors of rockfill. This model was applied to analysis of the stress in the concrete face slabs of the Shuibuya concrete faced dam and its settlement deformation. The calculations show that the model can well describe the behaviors of dilatation, shrinkage and creep of different rockfill materials under all kinds of loading conditions tested in this study. The creep of rockfill causes an increase in dam deformation and a stress growth in concrete face slabs, with the greatest effect on the slab＇s axial tensile stress of an increase up to 30%, and the second greatest on its stress along the slab slope. The creep effect on a high dam above 200 m has not yet completely decayed even after five years of full storage operation. Analysis of our field observation data reveals that the wetting-drying cycle of exposure to sun and rain could lead to longtime deformation of rockfill materials. This factor is neglected in our creep model, and therefore the simulated creep effects are smaller than the measurements.

关 键 词：堆石料 双屈服面流变模型 面板堆石坝 有限元 数值模拟 

分 类 号：TV147[水利工程—水力学及河流动力学]