黏滞阻尼器有效刚度对结构的影响及其取值方法研究

Study on influence of effective stiffness of viscous dampers on structure and its evaluation method

目前,在进行消能减震结构分析时,通常忽略黏滞阻尼器的刚度,影响了结构受力与响应的准确性。为此,阐述黏滞阻尼器刚度特性及其对结构的影响,给出一种适用于时程分析的有效刚度迭代取值方法。对设置黏滞阻尼器消能减震模型、附加有效阻尼比等效模型和附加有效阻尼比与有效刚度等效模型的三组模型进行分析,研究黏滞阻尼器有效刚度对结构受力与响应的影响。结果表明:采用附加有效阻尼比与有效刚度等效模型分析得到的结构楼层剪力与层间位移角的变化趋势基本和采用消能减震模型分析的结果一致;采用附加有效阻尼比等效模型与采用消能减震模型分析的结果则相差较大;时程分析中采用提出的有效刚度迭代取值方法是可行的,建议黏滞阻尼器消能减震结构设计时考虑黏滞阻尼器有效刚度的影响。

At present,in the analysis of energy dissipation structures,the stiffness of viscous dampers is often ignored,which affects the accuracy of structural force and response.Based on this,the stiffness characteristics of viscous damper and its influence on the structure were explained,and an iterative value method for time-history analysis of effective stiffness was given.Three sets of models,including energy dissipation model with viscous dampers,equivalent model with additional effective damping ratio and equivalent model with additional effective damping ratio and effective stiffness,were analyzed to study the influence of effective stiffness of viscous dampers on the force and response of structures.The results show that the variation trend of shear force and inter-story drift obtained by using the equivalent model with additional effective damping ratio and effective stiffness is basically consistent with those obtained by using the energy dissipation model.But the variation trend of shear force and inter-story drift obtained by using the equivalent model of additional effective damping ratio is not much consistent with those obtained by using the energy dissipation model.It is feasible to use the iterative value method of effective stiffness proposed for time history analysis.It is suggested that the influence of effective stiffness of viscous damper should be considered in the design of energy dissipation structure with viscous dampers.