充水保压蜗壳结构保压值优化研究

Study on Optimization of Preloading Water Head of Preloading Filling Spiral Case

以有限元软件Abaqus为分析平台,对某抽水蓄能电站充水保压蜗壳结构,建立了三维有限元模型,分析其在不同保压值下的钢衬应力、外围混凝土应力、钢蜗壳与混凝土之间的缝隙值、混凝土承载比及其损伤方面的情况.结果表明:选用较高的保压水头可有效降低外围混凝土的承载比,混凝土损伤带明显减小,钢衬的材料性能也得到了充分发挥.但是当保压值过高时,蜗壳与混凝土则处于脱开状态,考虑到蜗壳自振的特性,过高保压值对机组稳定性不利.通过5种保压值方案的比较,选取保压值为5.73MPa,即最大静水头的0.8倍较为合理,结论可为类似工程设计提供参考.

Based on the finite element software Abaqus,a three-dimensional finite element model is established for the preloading filling spiral case of a pumped storage power station.The stress of steel liner, surrounding concrete,gap value between steel spiral case and concrete,bearing ratio and damage of concrete are analyzed under different preloading water head.The results show that higher preloading water head can effectively reduce the bearing ratio and damage zone of concrete,and the material properties of steel liner have been given full play.However,when the preloading water head is too high,the spiral case and concrete are in the state of detachment.Considering the natural vibration characteristics of spiral case,too high preloading water head is unfavorable to unit stability.Through the comparison of five kinds of preloading water head,so select 5.73 MPa,that's 0.8 times of the maximum static water head.The conclusion can be used as a reference for similar engineering design.