藏式古建筑木梁-石墙节点弯矩-转角力学模型  

Moment-rotation mechanical model of timber beam-stone wall joints in Zang-style historic building

作　　者：崔玥 杨娜[1] 郭婷 CUI Yue;YANG Na;GUO Ting(School of Civil Engineering,Beijing Jiaotong University,Beijing 100044,China;Inspection and Certification Co.,Ltd,MCC,Beijing 100088,China)

机构地区：[1]北京交通大学土木建筑工程学院,北京100044 [2]中冶检测认证有限公司,北京100088

出　　处：《建筑结构学报》2024年第9期240-252,共13页Journal of Building Structures

基　　金：中央高校基本科研业务费专项资金项目(2021JBZ110);国家自然科学基金面上项目(51778045,51878034);高等学校学科创新引智计划项目(B13002)。

摘　　要：藏式古建筑中木梁与石墙洞口呈简单搭接关系,该类木梁-石墙节点连接薄弱,震坏风险高。以藏式古建筑中的木梁-石墙节点为研究对象,分析其建造过程,剖析其受力机制,给出正反向转动过程中的受力状态判定条件,建立了木梁-石墙节点的弯矩-转角力学模型;通过与有限元模型的对比分析,验证该力学模型的准确性。研究结果表明:建造过程中木梁头顶面与墙洞口之间存在缝隙;木梁-石墙节点的转动过程分为自由转动状态(木梁头在洞口内小幅度自由转动),临界状态(木梁头顶面、底面均与墙洞口接触),挤压状态(木梁顶面、底面弹性变形,木梁头顶面木材嵌压屈服,木梁头底面木材嵌压屈服)等3部分;根据所提木梁-石墙节点力学模型实现算法可快速完成实际节点的弯矩-转角关系计算;理论计算的木梁-石墙节点弯矩-转角曲线与有限元模拟曲线吻合较好,初始刚度误差小于30%,峰值荷载误差小于10%。In Zang-style historic buildings,timber beams and stone wall openings were simply lapped together.These timber beam-stone wall joints were weakly connected,resulting in a high risk of damage during earthquakes.The study focused on the timber beam-stone wall joints in Zang-style historic buildings,analyzed their construction process and force mechanisms.The force state determination conditions during forward and reverse rotation were provided.A moment-rotation mechanical model for the timber beam-stone wall joints was established.The accuracy of the mechanical model was validated by comparing with the finite element model.The results show that there is a direct gap between the top of the timber beam and the opening of the wall during construction.The rotation process of the timber beam-stone wall joint is divided into three parts:free rotation state(the timber beam head rotates freely in the hole with a small amplitude),critical state(the top and bottom surface of the timber beam head are in contact with the wall opening),and extrusion state(elastic deformation of the top surface and bottom surface of the timber beam,wood inlay yield on the top surface of the timber beam head,and timber inlay compression yield on the bottom surface of the timber beam head).According to the proposed mechanical model of the timber beam-stone wall joints,the bending moment rotation angle relationship of the actual joints can be calculated quickly.The theoretical calculated results of the bending moment angle curve of the beam-wall joints is in good agreement with the finite element simulation results,with an initial stiffness error less than 30%and a peak capacity error less than 10%.

关 键 词：藏式古建筑 木梁-石墙节点 力学模型 数值模拟 弯矩-转角关系 

分 类 号：TU363[建筑科学—结构工程] TU311.41