二滩高拱坝坝基灌浆帷幕防渗效果研究

Seepage Prevention Effect of Grouting Curtain of Ertan High Arch Dam Foundation

以运行期的二滩拱坝为例,考虑高拱坝坝基存在断层及有自由面排水孔幕情况,利用三维渗流场有限元模拟法、改进排水子结构法和隐式复合材料单元法建立了高拱坝坝基渗流场有限元数值模型,模拟了灌浆帷幕和排水孔幕同时作用时的拱坝实际渗流场,再假设坝基灌浆帷幕失效模拟了该工况下的坝基渗流场,通过比较分析研究了高拱坝坝基灌浆帷幕的防渗效果。结果表明,灌浆帷幕失效后二滩高拱坝坝基渗流场依然可在排水孔幕作用下保持稳定,坝肩部位渗流场稳定性明显降低。

Taking Ertan arch dam in operation period for an example, seepage prevention effect of grouting curtain of high arch dam foundation is studied. Three-dimensional seepage field FEM simulation method, improved drainage sub-structure method and latent complex-material element method are used to establish FEM seepage field numerical model of high arch dam foundation by considering faults and drain hole curtain with free surface in high arch dam foundation. And the actual seepage field of arch dam is simulated under the action of grouting curtain and drain hole curtain. Then theseepage field of dam foundation is simulated when the grouting curtain is failure. Finally, the seepage prevention effect of grouting curtain of high arch dam foundation is comparative analysis. The results show that when grouting curtain failedto work, seepage field of Ertan high arch dam foundation can also keep stable under the action of drain hole curtain while stability of the seepage field of dam abutment decreases obviously.