河床式厂房结构动力分析计算模型研究

Study on Dynamic Analysis Model of Run-of-river Powerhouse Structure

结合桐子林水电站河床式厂房,采用三维有限元法开展计算模型基岩范围、边界条件、材料动参数等因素对河床式厂房结构动力计算的影响分析。研究成果表明:计算模型中选取1.5~2.0倍厂房高度的基岩,并在基岩上下游端面和底部施加人工边界进行计算,可以使得计算工作的规模和计算结果的精确性达到最好的平衡;河床式厂房的边界采用人工边界模拟时,人工边界消耗掉了振动能量,厂房典型部位的振动响应减弱,采用人工边界模拟的方法更加符合实际情况;材料动弹性模量及阻尼比的取值对厂房的动力特性影响较小。随着动弹模的增大,厂房结构自振频率会有所提高,振幅有所减小。

Based on the run-of-river powerhouse of Tongzilin hydropower project,using three-dimensional finite element method to study the influence of bedrock range,boundary condition and material dynamic parameters on the dynamic analysis of powerhouse structure. The study results show: when the range of bedrock selected 1.5 ~ 2.0 times of powerhouse height in the calculation model,and the artificial boundary is applied at the upstream,downstream and bottom of the bedrock can provide the best balance between the scale and the accuracy of the calculation. When the boundary of the run-of-river powerhouse is simulated by artificial boundary,the vibration energy is dissipated,and the vibration response of the typical part of the powerhouse is weakened. The method of artificial boundary simulation is more effective. The dynamic elastic modulus and damping ratio of the material have little effect on the dynamic characteristics of the powerhouse structure. With the increase of the dynamic modulus,the natural frequency of the structure will increase,and the amplitude will decrease.