胶凝砂砾石坝应力及变形特点研究

Study on Stress and Deformation Characteristics of Cement-sand-gravel Dam

为了研究胶凝砂砾石坝应力和变形的特点,基于摩尔-库伦软化模型和混凝土弹塑性损伤本构模型,设置正常蓄水和超载2种工况对守口堡胶凝砂砾石坝的坝体模型进行有限元分析,并将正常蓄水工况结果与物理模型试验结果进行对比,探究该胶凝砂砾石坝的应力和应变特点。结果表明:正常蓄水工况下,该大坝的应力和变形结果与模型试验结果相近,应力及位移的分布规律、大小基本一致,该结果验证了数值模拟结果的准确性;超载工况下,该大坝的这2种本构模型的应力和应变计算结果相近,应力和位移分布规律一致,且均在坝踵处出现损伤,均未出现整体破坏的情况,说明守口堡胶凝砂砾石坝设计合理,抗压和抗拉特性良好。其模型试验结果及数值模拟结果可为工程实际提供参考。

In order to study the stress and deformation characteristics of cement-sand-gravel dam, and based on Mole-Coulomb constitutive model and elastoplastic damage constitutive model of concrete, the finite element analysis of the dam model was carried out under two conditions of normal water storage and overload. Then compared the finite element by normal water storage with physical model test results to study the stress and strain characteristics of cement-sand-gravel dam. The results show that the results of stress and deformation under normal static water load are similar to the model test results, also the distribution law of stress and displacement are basically same, which firstly proves the accuracy of the numerical simulation results. Secondly, based on two constitutive models, the calculation results of stress and strain under the overload condition are similar, and the distribution laws of stress and displacement are same. In addition, damage occurs at the dam heel, and overall damage doesn′t occur. These show that the design of cement-sand-gravel dam of Shoukoubao is reasonable with pretty good compressive and tensile properties, and the results of the model test and the numerical simulation can provide a reference for engineering practice.