附加油阻尼器的非线性滞回结构系统的等价线性化方法
Equivalent Linearization Method for Nonlinear Structure System Added with Oil Damper

以安装油阻尼器的单自由度非线性滞回结构系统为研究对象，建立地震作用下该非线性结构系统的等价线性化方法。鉴于结构系统具有双非线性特征，其中油阻尼器的阻尼力与速度呈双线性关系，主体结构具有双线性滞回特征，将主体结构等价为线性Kelvin模型，附加体系分两步等价：将双线性黏滞单元等价为线性黏滞单元，得到含线性黏滞单元的附加体系与主体结构的Kelvin模型并联构成的等价模型A；基于模型A进一步求解系统的等价刚度和等价阻尼比，建立系统的等价线性化Kelvin模型，即模型B。通过共振曲线分别对模型A和模型B的精度进行了验证。考虑地震动的随机性，通过动力非线性时程分析对等价模型的阻尼比公式进行了修正。将等价线性化方法应用到性能曲线中，建立非线性结构系统的减震性能曲线绘制方法，结合性能曲线分析了油阻尼器对非线性结构的减震效果。结果表明：模型A与模型B的共振曲线与原结构均吻合，说明在非线性结构系统中将双线性黏滞单元等价为线性黏滞单元的方法可行；修正后的等价阻尼比可较好地预测地震作用下非线性结构系统的最大位移。
Taking the single degree of freedom nonlinear structure system added with oil damper as study object, an equivalent linearization method of the nonlinear structure system under earthquake was proposed. The structure system behaved bi？？linearly character, the relationship between damping force and velocity of oil damper was bi？？linear, and the main structure behaved bi？？linearly hysteretic characteristics. The main structure was equated to a linear Kelvin model, and the added system was equated in a two？？step way: bi？？linearly viscous element was equated to a linearly viscous element, then the added system with linear viscous element was connected to the Kelvin model of main structure in parallel, namely model A; based on model A, the equivalent damping ratio and equivalent period were derived, and the system was equated simply to a Kelvin model, namely model B. The accuracies of the two models were investigated by comparing the resonance curves, respectively. Considering the randomness of earthquake excitation, the equivalent damping ratio computed from model B was further revised based on nonlinear time history analysis. The equivalent linearization method was expanded to performance curves, and the drawing method for damping performance curves of nonlinear structure system was established. The damping effect of oil damper on nonlinear structure was analyzed combined performance curves. The results show that the resonance curves of model A and model B both coincide the original structure respectively, which proves bi？？linearly viscous element equivalent to a linearly viscous element in nonlinear structure is feasible. The revised equivalent damping ratio can effectively predict the peak displacement of nonlinear structural systems under earthquake