淤积固结条件下坝前泥沙压力对坝体影响的试验  

Effects of sediment pressure on dam under conditions of deposition and consolidation

作　　者：陈一明[1] 谈广鸣[1] 

机构地区：[1]武汉大学水资源与水电工程科学国家重点实验室,湖北武汉430072

出　　处：《武汉大学学报（工学版）》2014年第2期145-148,176,共5页Engineering Journal of Wuhan University

摘　　要：首次对坝前泥沙压力在淤积固结作用下的变化规律进行了分析研究.初步分析了坝前泥沙在水库运行影响下的淤积特征.通过模型试验并在理论分析的基础上分析了坝前泥沙淤积固结机理及相应泥沙压力,得到了坝前泥沙饱和容重随时间的变化规律及最终的稳定趋势.结果表明:坝前泥沙经过一定的淤积历时后,容重分布发生了较大变化,深层淤积泥沙容重显著增大.为了描述这一变化规律,拟合了试验条件下泥沙容重随时间变化的公式.并经有限元计算,对比分析了重力坝在无泥沙淤积的运行初期、泥沙淤积初期以及泥沙经过固结作用达到稳定容重的后期等3种工况下的应力状态,得到了坝前泥沙压力在淤积固结作用下对坝体稳定有一些不利影响的结论.The variation of sediment pressure in front of dam under deposited and consolidated conditions were firstly analyzed by modeling test; and then the saturated unit weight of sediment varying with time and its final stable trend were obtained. It turns out that there exists a great transformation on the unit weight distribution; and the deeper density increased significantly after the sediment deposition. In order to describe the variation, a formula of sediment unit weight varying with time was fitted under the experi- mental conditions. Based on the results of the finite element analysis, the comparisons of the three cases on sediment stress： the preliminary stage without deposition, the medium stage when sediment begin to deposit, and the final stage when the unit weight of sediment reached to equilibration during the sedimentation process, are investigated. The results show that the sediment pressure of dam under the conditions of deposition and consolidation has some negative effects on the stabilization of dam.

关 键 词：粘性泥沙 泥沙压力 淤积固结 坝体稳定 

分 类 号：TV145[水利工程—水力学及河流动力学]