强震区软基上泵站地下连续墙注浆加固方案研究

Study on the Grouting Reinforcement of Underground Continuous Retaining Wall for the Pumping Station on the Soft Foundation in the Area with High Earthquake Intensity

为解决高地震烈度区睢宁泵站软弱地基问题,提出了一种新型板肋式地下连续墙与土体注浆加固的设计方案。结合泵站结构的布置特点,建立了三维非线性有限元计算模型,分别从肋宽、注浆深度和土体强度参数的提高幅度这3个方面,对板肋式地下连续墙的水平位移进行了静、动力有限元分析。结果表明,板肋式挡墙结构在墙背土体注浆深度为19.5 m、土体变形模量提高10倍以上、粘聚力提高1.5～2倍和内摩擦角增加2°～4°时,墙体的水平位移便能得到有效的控制。通过实例研究,验证了该加固方案的合理性和有效性。

In order to solve the problem of soft foundation of Suining Pumping Station in the area with high earthquake intensity, this paper presents a new design scheme for sheet-rib underground continuous retaining wall and reinforcement grouting. According to the arrangement features of the structure of pumping station, a 3D nonlinear finite element model was set up and the static and dynamic finite element analysis were carried out on the horizontal displacement of sheet-rib underground continuous retaining wall from three different aspects of rib width, the depth of grouting and soil strength parameters. Results showed that the horizontal displacement of sheet-fib underground continuous retaining wall can be effectively controlled when the grouting soil depth reaches up to 19.5m and the soil body increases its deformation modulus E by 10 times, cohesive force C by 1.5-2 times and internal friction angle φ by 2°-4°. The case studies showed that this reinforcement scheme is reasonable and effective.