高层钢结构不同减震加固方案的抗震韧性评估

Assessment of reinforcement scheme for a high-rise steel structure based on seismic resilience and reinforcement benefit ratio

随着既有建筑减震加固需求的不断增加,如何从抗震韧性的新角度评估减震加固方案的合理性成为一个需要关注的问题。该文以一栋高层钢结构减震加固为例,从抗震韧性的角度对两种减震方案进行对比。首先基于数学算法,从PEER(Pacific Earthquake Engineering Research Center)地震动数据库中选取20条地震波,使所选地震动的加速度反应谱均值和目标谱吻合,并实现每条反应谱在结构基本周期点和目标谱完全吻合;通过3000次蒙特卡洛模拟,得到修复费用、修复时间和伤亡率的对数正态分布函数,并取84%分位值作为代表值,以比较两种加固方案的优劣;提出加固收益率的概念,并从加固收益的角度重新评估两种方案的经济效益,结果表明阻尼器较多的加固方案可能造成加固成本大于修复成本,使阻尼器数量较少的加固方案更加经济合理。该文的工作是抗震韧性在减震加固中方案评估中的应用,完善减震加固理论体系,为抗震韧性的在减震加固工程中的应用提供借鉴。

With the increasing demand for seismic strengthening of existing buildings,it has become a concern to evaluate the seismic strengthening schemes based on the seismic resilience.Taking a high-rise steel structure as an example,the presented paper compares two seismic strengthening schemes from the perspective of seismic resilience.Firstly,20 seismic waves are selected from PEER earthquake ground motion database by the greedy algorithm to make their average acceleration response spectrum coincide with that of target acceleration response spectrum.Through the Monte Carlo Simulation,the lognormal distribution functions of repair cost,repair time,hurt ratio and death ratio are obtained,and the 84% fraction values are taken as representative values to evaluate the two reinforcement schemes.Finally,the two reinforcement schemes are further evaluated based on the proposed concept of reinforcement benefit ratio.The results indicate that the reinforcement scheme with more dampers may cause a higher cost,while the reinforcement scheme with fewer dampers is more economical.The main work conducted in the presented paper is the application of seismic resilience in the evaluation of seismic reinforcement schemes,which improves the theories of seismic reinforcement and provides reference for the further application of seismic resilience in seismic reinforcement practice.