小塘水电站闸坝及桩基础的变形特性研究

Study on Deformation Characteristics of Dam and Pile Foundation of Xiaotang Hydropower Station

桩基础是砂卵石地基闸坝的主要承载方式,闸坝及桩基础的变形特性直接影响到工程的安全性。结合小塘水电站闸坝工程,采用D-P非线性弹塑性本构模型及三维有限元法分析了典型工况下闸坝及桩基础的三维应力场和位移场,分析了结构的稳定性,揭示了闸坝区应力分布情况及变形规律。研究结果表明:运行工况下的闸室结构和灌注桩的位移值和应力水平比完建工况下的位移明显增大;在完建工况和运行工况下,闸室结构和地基的大部分区域处于压应力状态,且处于弹性状态;从应力水平、位移量值及塑性屈服区分布情况表明,小塘水电站闸室及灌注桩整体结构是稳定的。但在闸室的底部、灌注桩的两端部位存在一定的应力集中现象,建议进行适当的加固处理。研究成果可供类似工程参考。

The pile foundation is the main bearing mode of the sand pebbles foundation dam. The deformation characteristics of the dam and pile foundation directly affect the safety of the project. Combined with the dam project of Xiaotang Hydropower Station, the nonlinear elastic-plastic constitutive model and three-dimensional finite element method are used to analyze the three-dimensional stress field and displacement field of the dam and pile foundation under typical working conditions, and the stability of the structure is analyzed. Stress distribution and deformation law in the dam area. The results show that the displacement and stress levels of the lock chamber structure and the bored pile under operating conditions are significantly higher than those under the construction conditions;under the conditions of construction and operation, the structure of the lock chamber and the foundation Most of the regions are in compressive stress state and are in elastic state. The stress level, displacement magnitude and plastic yield zone distribution indicate that the overall structure of the lock chamber and the cast-in-situ pile of Xiaotang Hydropower Station is stable. However, there is a certain concentration of stress at the bottom of the chamber and at both ends of the pile. It is recommended to carry out proper reinforcement. The research results can be used as reference for similar projects.