渗流分析中基于Signorini变分不等式结合杆单元法的排水孔模拟

Rod Elements Method Based on Variational Inequality Approach of Signorini Type for Simulating Drainage Holes in Seepage Analysis

在水利水电工程中,排水孔幕是一项至关重要的渗控措施,而在数值模拟过程中排水孔模拟的准确性对工程的设计与安全有直接影响。利用有限元方法中含自适应罚函数的椭圆形Signorini变分不等式方法,结合在工程实践中运用广泛的杆单元法,对含排水孔的稳定渗流问题进行模拟。并基于若干个简单渗流算例与小湾工程实例,将计算结果进行对比分析。研究表明:排水孔周边均形成降落漏斗,模拟的排水孔均发挥了排水降压的效用;将算例计算结果与空气单元法模拟相同过程的结果进行对比,准确性较好;将小湾工程实例渗流场计算结果与工程监测资料进行对比,偏差较小,进一步证明了所提出方法的准确性与可靠性。为解决含有复杂排水结构的岩土体的三维渗流问题提供了一种可行方案。

During the design and construction stage of hydro-engineering project, the drainage hole curtain is a vital seepage control measure. The accuracy of the numerical simulation process has a direct impact on the design and safety of the project. In this paper, drainage holes are simulated by the rod element which gets widely used in engineering practice combing with the elliptic Signorini-type variational inequality finite element method. The calculation results based on several simple seepage cases and an example of Xiaowan Project are compared and analyzed. It's shown that: The cone of depression is formed around the drainage holes and the simulated drainage holes in this paper are effective in water draining and pressure releasing. In the seepage cases, compared with the results of the same process of the air element method, the suggested method has better accuracy. In the example of Xiaowan Project, the deviation of seepage field calculation results is small compared with the monitoring data of projects, which also demonstrates the reliability and veracity of the this method. It provides a feasible solution to the three-dimensional seepage problem of rock and soil with complex drainage structures.