数值计算模型对地下厂房动力特性的影响分析

Effects of Numerical Calculation Model on Dynamic Characteristics of Underground Powerhouse

结合某大型水电站地下厂房工程实际,采用三维有限元分析方法,对建立地下厂房结构动力分析数值计算模型涉及的混凝土动态弹性模量、阻尼比、围岩范围和边界条件对厂房结构自振特性和动力响应(动位移和动应力)的影响程度和规律进行了敏感性分析。计算结果表明:厂房整体结构自振频率受动态弹性模量取值、围岩范围和围岩边界条件影响较大,与阻尼比的取值无关;厂房结构动位移与动态弹性模量取值成反比,受围岩范围和边界条件的选择影响有限,受阻尼比取值影响很小;厂房结构动应力受动态弹性模量和阻尼比取值、围岩范围和围岩边界条件的选择影响很小。

Based on the underground powerhouse of a large-scale hydropower station,using three dimensional finite method to analyze the concrete 's dynamic modulus of elasticity,damping ratio,and the range of the surrounding rock and the boundary conditions on the structural self-vibration characteristics and dynamic response(dynamic displacement and dynamic stress) sensitivity. The results indicate that the natural frequency of power house structure is greatly influenced by dynamic modulus of elasticity,the range of the surrounding rock and the boundary conditions. The dynamic displacement of power house structure is inversely proportional to dynamic modulus of elasticity and affected limited by the range of the surrounding rock and the boundary conditions. The dynamic stress of power house structure is weakly dependent on dynamic modulus of elasticity,the range of the surrounding rock and the boundary conditions.