含透水层渠基的挖方渠道渗控措施研究

摘要

Aiming at the seepage problem of excavated main canal with permeable foundation at Taocha-Lushan section of Middle Route Project of South-to-North Water Diversion, the influence of strong permeable layer on canal stability in construc-tion and operation period was analyzed. According to the distributing characteristics of permeable layers, the seepage analysis on typical cross-section of 4 types canal foundations was conducted combining with the canal structures and seepage control require-ments in different periods. The seepage model was established using FEM and calculated by Seep2D software. The seepage con-trol effect of dewatering well and cutoff wall were analyzed and compared according to the calculation results and the correspond-ing measures were put forward. The engineering practice shows that the dewatering effect is obvious, which can guarantee the safe water delivery.%针对南水北调中线工程陶岔至鲁山段含透水层渠基的挖方渠道渗流问题，分析了强渗漏层对施工期、运行期渠道稳定性的影响。根据渠基透水层的分布特点，结合渠道的工程结构和不同时期的渗控要求，采用有限元法建立渗流模型，并利用Seep2D渗流模块对4类渠基的典型断面进行渗流分析。根据计算结果，对比分析了降水井和防渗墙方案的渗控效果，并提出相应渗控措施。工程实践表明，渗控措施的降水效果明显，能够有效保证渠道正常输水。