水电站充水保压蜗壳仿真分析的影响因素

基于接触非线性理论，考虑钢蜗壳与外围混凝土的接触滑移，采用仿真算法对充水保压蜗壳进行了三维仿真分析和平面轴对称仿真分析．研究了机墩和设备质量及平面轴对称简化模型对蜗壳打压后的变形、蜗壳与混凝土的间隙及其应力的影响．计算结果表明：机墩及设备质量对钢蜗壳的应力影响较小，但对钢蜗壳号外围混凝土的间隙和外围混凝土的应力影响较大，三维仿真模型应该考虑机墩及设备的质量；平面轴对称仿真模型虽未考虑闷头在仿真分析中的作用，但能反映钢蜗壳和外围混凝土的变形特征与受力特性，可以在初步设计时采用．

Factors influence on simulation analysis of preloading filling spiral cases in hydropower stations

On the basis of surface-to-surface contact nonlinear theory,the contact slippage between spiral case and surrounding concrete was considered.Three-dimensional simulation and plane axisymmetric simulation of preloading filling spiral case were analyzed.The influence of generator piers and the weight of equipments and plane axisymmetric simplified model on three aspects,deformation of steel spiral case under preloading filling pressure,gap value between spiral case,and surrounding concrete and their stress,were studied.The results show that weight of generator piers and equipments has little impact on spiral case stress but great impact on the gap value between spiral case and surrounding concrete and the stress of surrounding concrete.Three-dimensional simulation model should consider generator piers and the weight of equipments.Plane axisymmetric simulation model has not yet considered the role of bulkhead in the simulation analysis but can basically reflect the deformation and mechanical characteristics of spiral case and surrounding concrete,which can be adopted in the preliminary design.