【摘要】 某面板堆石坝施工期基坑发生严重渗水,影响施工正常进行。检查发现下游导流明渠由于施工质量问题,出现局部开裂导致漏水,并且漏水处下部粉土质砂发生塌陷。采用有限元法,对上游围堰、堆石坝基坑和导流渠道进行了数值建模和三维渗流场计算分析。通过对比渠道正常运行和带缺陷运行的三维渗流场和土体渗流比降的变化,揭示了渠道漏水对整体渗流场和渗流量的影响,论证了塌陷产生的原因。提出了加深防渗墙和提高渠道施工质量的建议。更多还原

【Abstract】 The foundation pit of a concrete faced rock-fill dam(CFRD) project had seen serious seepage which affected the construction.It was found that cracks and leakage occurred at the lower open diversion channel due to bad construction quality,which had led to collapse of below silt soil.Numerical model was established and three-dimensional seepage analysis was conducted by finite element method for the upstream cofferdam,foundation pit and diversion channel.By comparing the changes of 3D seepage field and soil seepage gradient between channel in normal state and that with cracks,the authors demonstrate the impact of leakage at channel on the overall flow field and seepage discharge,discuss the causes for collapse,suggest to deepen the anti-seepage wall and improve the construction quality of channel.更多还原