丹江口大坝右岸转弯坝段横缝切缝计算分析

The Effect of Joint-Cutting on Turning Dam Section at the Right Bank of Danjiangkou Dam

为分析坝体反向变形成因以及不同切缝措施对坝体变形、坝体上游面应力的影响,以丹江口大坝右岸混凝土坝转弯坝段为研究对象,采用三维线弹性及非线性有限元分析方法,计算得到不同横缝切缝位置、条数和深度时的坝体位移与应力。结果表明:初期灌浆将转弯坝段连成整体形成的拱效应是产生反向变形的主要原因;从减小或消除转弯坝段反向变形,改善上游面高程143m处竖向应力角度考虑,建议进行切缝处理,切缝深度至高程140 m左右。

To analyze the cause of the reverse deformation and the effect of different joint-cutting measures on the dam deformation and upstream surface stress,this paper takes the turning dam section at the right bank of Danjiangkou Dam as the research object,and carries out numerical simulations with 3-D linear and nonlinear FEM.The dam displacements and stresses under various joint-cutting locations,different numbers and depths are put forward.The computation results show that arch effect caused by the grouting in early stage is the main cause of the reverse deformation of the turning dam section.In order to reduce or eliminate the reverse deformation and improve the upstream surface stress at EL.143 m,it is recommended that joint-cutting measures should be taken,and joint cutting depth should be reached around EL.140 m.