【摘要】 为了解决单一常系数弹簧-阻尼器并联系统表征的场地动力模型无法反映无限域场地的动刚度和阻尼是随激振频率变化的函数,也无法反映非均质场地条件影响的问题,从谐响应动力求解方法的基本概念出发,以粘弹性场地动力模型为分析对象,推导了一种适于非均质场地条件的随激振频率变化的核电厂地基动阻抗数值的求解方法,并分别以二维和三维算例的形式给出了该方法和传统抗震设计规范集总参数模型结果、经典解的比较。结果表明:采用该方法计算的动阻抗满足工程精度要求且能表征出地基动阻抗是随激励频率改变而变化的。更多还原

【Abstract】 In the framework of lumped parameter numerical models,the traditional soil dynamic models were only expressed by a single parallel connection system of spring and damper,which could not reflect the dynamic stiffness varying with excitation frequencies,and could not simulate the cases of nonhomogeneous site conditions.Based on the essential concepts of dynamic solution method of harmonic response,an improved numerical solution to the dynamic impedance of foundation for nuclear power plant was presented by using viscoelastic soil dynamic model,which was especially fit for the numerical simulation of nonhomogeneous soil condition,and gave the dynamic impedance of foundation varying with the excitation frequencies.To solve the problems of 2-D and 3-D types,some numerical examples were given to validate its accuracy and applicability by comparing the method with the classical solutions and lumped parameter model suggested by seismic design codes.The results show that the dynamic impedance calculated by the method can satisfy the engineering precision,and the method can take dynamic impedance of foundation changed with excitation frequencies.更多还原