随机地震动作用下结构-TMDI系统参数设计与概率密度演化分析

Parameter design and probability density evolution analysis of structure-TMDI system subjected to stochastic earthquake ground motions

针对随机地震动作用下结构-调谐质量惯容阻尼器(TMDI)系统参数设计与概率密度演化分析开展研究。首先采用定点理论公式和基于遗传算法的数值优化方法,结合规范选波进行低惯质比、中惯质比和高惯质比TMDI参数优化。在此基础上,结合概率密度演化理论与物理随机地震动模型,进行随机地震动作用下结构-TMDI系统概率密度演化分析,并比较具有相同质量比的常规调谐质量阻尼器(TMD)的减震性能。算例分析表明:定点理论公式不能合理设计结构-TMDI系统,基于遗传算法的数值优化方法能高效、可靠地获得最优阻尼器参数;相同等效质量比的TMDI比TMD的减震性能更优越,结构可靠度显著提升,达到安全性设计要求;同时,TMDI仅采用了TMD设计1/50的物理质量,且仅需40%的冲程设计要求。文章研究在概率意义上揭示了TMDI增效、减质、限程的技术优势。

Parameter design and probability density evolution analysis of a structure-tuned mass damper-inerter(TMDI)system subjected to stochastic earthquake ground motions are studied.Firstly,the fixed-point theoretical formula and the genetic algorithm-based numerical optimization method are used,and the parameters of low,medium and high inertermass ratio are optimized in combination with the canonical seismic wave-selection method in design code.On this basis,by combining the probability density evolution method with the physically-motivated stochastic earthquake ground motion model,the probability density evolution analysis of the structure-TMDI system under the action of stochastic earthquake ground motion is carried out,and the shock absorption performance of the conventional tuned mass dampers(TMD)with same mass ratios is compared.Numerical analysis results show that the structure-TMDI system may not be reasonably designed by the fixed-point theoretical formula,while the optimal damper parameters can be efficiently and reliably obtained by the genetic algorithm-based numerical optimization method.TMDI is superior to TMD with the same equivalent mass ratios,and the structural reliability can be significantly improved,so that the requirements of safety design can be met.Moreover,TMDI needs only 1/50 of the physical mass and 40%of the stroke design requirement of TMD.The technical advantages of TMDI in the performance improvement,mass reduction and stroke limitation are revealed in the sense of probability.