考虑残损的古建木结构地震易损性分析  

Seismic fragility analysis of timber structure considering initial damage

作　　者：杨娜[1] 谭圣 秦术杰 YANG Na;TAN Sheng;QIN Shujie(School of Civil Engineering,Beijing Jiaotong University,Beijing 100044,China)

机构地区：[1]北京交通大学土木建筑工程学院

出　　处：《世界地震工程》2019年第4期95-104,共10页World Earthquake Engineering

基　　金：国家自然科学基金面上项目(51778045)

摘　　要：现役古建木结构普遍存在残损现象,这将影响结构的抗震性能。本文以北京故宫的咸福宫西配殿为研究对象,通过简化其屋顶、斗拱、榫卯和柱脚节点建立结构的理想模型,并在此基础上考虑材料老化和节点性能降低等因素建立其残损现状模型。通过地震易损性分析,得到古建木结构的地震易损性曲线并进行理想和残损结构的震害等级及其发生概率对比。研究结果表明:残损现象降低了咸福宫西配殿的刚度和自振频率;相比于理想结构,咸福宫西配殿残损结构在小震作用下发生轻微损坏的概率增大21.1%,在中震作用下发生中等破坏的概率增大3.7%,大震作用下发生严重破坏的概率增大10.6%;咸福宫西配殿在大震作用下发生倒塌的概率很小,体现了木结构具有良好的抗震性能。There always are different degrees of damage in the existing ancient timber buildings,which will reduce the structural seismic performance.In this paper,the western side-hall of Happiness Palace in Forbidden City was chosen for study.The intact model of structure was established by simplifying the roof and the key joints including Dougong,mortise-tenon connection and column foot,with the damaged model established considering the influencing factors such as materials aging and connecting performance degradation of key joints.The structuralfragility curves were obtained based on seismic fragility analysis,and the earthquake damage level and occurrence probability of intact and damaged structures were compared.The results showed that the damage phenomena will reduce the stiffness and natural frequency of ancient timber structures.Compared with the intact structure,the probability of suffering minor damage for damaged structure under the minor earthquake had an increase of 21.1%,and with probabilitiesincrease of 3.7%and 10.6%of suffering moderate and serious damage under the moderate and major earthquake,respectively.Both the collapse probabilities of intact and damaged structures under the major earthquake were low,which reflected the excellent seismic performance of ancient timber buildings.

关 键 词：古建木结构 残损 时程分析 地震易损性分析 

分 类 号：TU366.2[建筑科学—结构工程]