广义阻尼模型及其在混凝土重力坝地震响应分析中的应用

基于黏弹性材料的广义流变模型，推导出一种广义阻尼模型及相应的结构动力学方程，分别选用指数函数和高斯函数为广义阻尼模型的卷积核函数，采用Newmark直接积分法计算了Koyna大坝的地震响应，分析了松弛参数、时间积分步长对大坝地震响应的影响，比较了广义阻尼模型和黏滞阻尼模型情况下大坝的地震响应。结果表明：地震作用下广义阻尼模型的响应峰值均大于黏滞阻尼模型的响应峰值；松弛参数越大，广义阻尼的响应峰值越接近黏滞阻尼的响应峰值；指数模型对数值积分时间步长的要求高于高斯模型。

A generalized damping model and its application in seismic response analysis of concrete gravity dam

Based on the generalized rheological model of viscoelastic materials, a generalized damping model and the dynamic equilibrium equation of structure are derived. The exponential function and Gaussian function are selected as the convolutional kernel functions of the generalized damping model. The seismic response of the Koyna Dam is calculated by the Newmark direct integration method, and the effects of relaxation parameter and time integration step on the seismic response of the dam are also analyzed. Seismic responses of the dam with the generalized damping model and the viscous damping model are compared at last. The results show that the seismic peak response with the generalized damping model is greater than that with the viscous damping model, and the larger the relaxation parameters, the closer the peak response with the generalized damping is to that with the viscous damping. Meanwhile, the exponential model has higher requirements for the time step of numerical integration than the Gaussian model.