土石坝防渗(复合)土工膜缺陷及其渗漏问题研究进展

Advances in research of defects and leakage of( composite ) geomembrane in earth-rock dams

在国内外众多土石坝采用(复合)土工膜防渗的工程背景下,分析了坝面或坝内土工膜缺陷的类型及产生缺陷的原因。归纳总结了国内外已有(复合)土工膜缺陷渗漏问题的研究成果,认为现有研究成果不适用于解决高土石坝复合土工膜的缺陷渗漏问题。同时认为高土石坝复合土工膜的缺陷演化规律、缺陷渗漏对坝体渗流场分布及对大坝安全的影响,以及如何采取有效的限渗减漏措施预防和减小缺陷渗漏量,已成为高土石坝复合土工膜防渗工程发展的瓶颈。为此,建议对复合土工膜的缺陷渗流特性进行试验研究,同时采用理论分析、数值模拟和工程实例反馈分析等手段对土石坝中复合土工膜的缺陷渗流及缺陷演化等相关问题进行系统研究,以便为复合土工膜防渗高土石坝的渗漏安全评判、预防及修复等方面起到理论指导作用。

In the context of ( composite) geomembrane being widely used in many earth-rock dams in China and abroad, the reasons for defects and defect classification in geomembrane on the dam surface or inside dams are discussed. Based on a summary of research on the defects and leakage of ( composite) geomembrane in China and abroad, it is shown that the existing results cannot be directly used to solve the defect and leakage problems of composite geomembrane used in high earth-rock dams. It is also shown that defect evolution, the influence of defect-induced leakage on the dam seepage field distribution and dam safety, and effective measures for leakage control are the development bottlenecks for composite geomembrane application in high earth-rock dams. Therefore, laboratory tests should be performed to study the defect-induced leakage of composite geomembrane. It is also necessary to conduct systematic research on some issues related to defect evolution and defect-induced leakage in composite geomembrane used in earth-rock dams based on theoretical analysis, numerical simulation, and feedback analysis of practical projects, so as to provide guides for leakage prevention and restoration of composite geomembrane as well as safety evaluation of high earth-rock dams with composite geomembrane used for seepage control.