随机地震作用下BRB加固既有结构的可靠度分析  

Reliability Analysis of Existing Structures Strengthened by BRB under Stochastic Earthquake

作　　者：闫龙 阮鑫鑫 刘章军 YAN Long;RUAN Xinxin;LIU Zhangjun(School of Civil Engineering and Architecture,Wuhan Institute of Technology,Wuhan 430074,China)

机构地区：[1]武汉工程大学土木工程与建筑学院,湖北武汉430074

出　　处：《防灾减灾工程学报》2023年第3期444-452,共9页Journal of Disaster Prevention and Mitigation Engineering

基　　金：国家自然科学基金面上项目(51978543);湖北省高等学校优秀中青年科技创新团队计划项目(T2020010)资助。

摘　　要：随着服役年限的增加,既有结构会出现材料力学性能经时退化。为精细化分析随机地震作用下既有结构及其加固后的安全性,利用非平稳地震动过程的降维模拟,并结合基于概率密度演化理论和等价极值分布的首次超越破坏可靠度分析方法,以层间位移角为评价指标,制定了3种在不同位置布设人字形BRB的加固方案。根据随机地震作用下BRB加固既有结构的动力可靠度来确定3种方案中的较优者。同时,依次用V字形和斜支撑替换较优方案中的人字形支撑,并对比分析它们的动力可靠度,以寻找最优随机非线性振动控制的BRB布设位置和支撑形式,为维修加固及抗震设计提供更为合理的途径。结果表明:本文方法为既有结构及其加固结构的抗震可靠度精细化计算提供了新途径,BRB的不同布设位置及支撑形式能在一定程度上提高既有结构的动力可靠性。With the increase of service life,the mechanical properties of existing structures will deteriorate over time.To finely analyze the safety of existing structures and their reinforced structure under stochastic earthquake activity,the dimension reduction simulation of non-stationary ground motion process is used,and the first excursion failure reliability analysis method based on probability density evolution theory and equivalent extreme value distribution are combined.Taking the inter-story drift ratio as the evaluation index,three reinforcement schemes of herringbone BRB at different locations are formulated.According to the dynamic reliability of BRB strengthening existing structures under random earthquake,the better of the three schemes is determined.At the same time,V-shaped support and inclined support are used to replace the herringbone support in the better scheme,and their dynamic reliability is compared and analyzed to find the optimal BRB layout position and support form for random nonlinear vibration control,to provide a more reasonable way for maintenance,reinforcement and seismic design.The results show that the method proposed in this paper provides a new way for the refined calculation of seismic reliability of existing structures and their reinforced structures,and the different layout positions and support forms of BRB can improve the dynamic reliability of existing structures to a certain extent.

关 键 词：既有结构 BRB加固 材料性能经时退化 随机地震作用 概率密度演化 动力可靠度 

分 类 号：P315.9[天文地球—地震学] TU375.4[天文地球—固体地球物理学]