平身科斗栱抗震性能试验研究及有限元分析  

Experimental study and finite element analysis on seismic behavior of Pingshenke Dou-Gong brackets

作　　者：薛建阳[1,2] 凌怀泉 宋德军 吴晨伟 郭瀚泽 XUE Jianyang;LING Huaiquan;SONG Dejun;WU Chenwei;GUO Hanze(School of Civil Engineering,Xi'an University of Architecture&Technology,Xi'an 710055,China;Key Lab of Structural Engineering and Earthquake Resistance,Ministry of Education XAUAT,Xi'an 710055,China)

机构地区：[1]西安建筑科技大学土木工程学院,陕西西安710055 [2]西安建筑科技大学结构工程与抗震教育部重点实验室,陕西西安710055

出　　处：《建筑结构学报》2023年第10期74-85,共12页Journal of Building Structures

基　　金：国家自然科学基金项目(52278317);陕西省自然科学基础研究重点项目(2020JZ-50);陕西省科技创新团队项目(2019TD-029)。

摘　　要：以沈阳故宫颐和殿单翘单昂五踩平身科斗栱为原型,参照清工部《工程做法则例》,制作了两攒足尺平身科斗栱。通过沿出踩和面宽方向加载的低周反复荷载试验,得到斗栱的破坏模式、滞回特性、刚度和承载力退化、延性及耗能性能。结果表明:斗栱的主要破坏特征是大斗与平板枋之间的馒头榫受剪破坏、大斗横纹受压劈裂以及单翘劈裂,枋与桁间拔榫,模型整体转动变形;沿出踩方向加载的斗栱捏缩效应明显,承载力和耗能较面宽方向差,两者刚度和承载力退化显著,但位移延性系数均值超过5.0,变形能力较强。建立斗栱有限元模型并进行数值模拟,模拟结果与试验结果吻合较好。进行了竖向荷载、摩擦系数、木材弹性模量和横纹径向抗压强度对斗栱抗震性能影响的参数分析,结果表明竖向荷载和摩擦系数越大,斗栱的抗侧刚度和承载力越大,而木材弹性模量和横纹径向抗压强度对模型抗侧刚度和承载力影响较小。The‘single-Qiao and single-Ang five-Cai'Pingshenke Dou-Gong bracket in the Yihe Hall of Shenyang Imperial Palace was selected as the prototype in this study.Two full-scale Pingshenke Dou-Gong specimens were fabricated,conforming to the‘Requirements of engineering fabrication method'of the Qing Dynasty.The failure modes,hysteretic characteristics,degradation of stiffness and strength,ductility and energy dissipation capacity of Dou-Gong brackets were obtained by the low cyclic reversed loading test in the overhanging and width directions.The results indicate that the main failure patterns of Dou-Gong brackets are the shear failure of Mantou-tenon(a kind of dowel)between Da-Dou(square timber blocks)and Pingban-Fang(a kind of beam under Da-Dou),the split of Da-Dou along the transverse grain and split of single-Qiao(rectangular square wood with circular arc),the tenon pulling between Fang(rectangular square wood)and Heng(cylindrical wood),and the rotation deformation of the whole model.The pinching effect of Dou-Gong bracket in the overhanging direction is obvious,and the bearing capacity and energy dissipation in this direction are worse than the width direction of Dou-Gong bracket.The stiffness and strength degradation of the two specimens are apparent,and the average displacement ductility coefficient is about 5.0,showing good deformation capacity.A finite element model of Dou-Gong brackets was built to conduct numerical simulation analysis,and the simulation results are in a good agreement with the test results.Parameter analysis considering the effects of the vertical load,friction coefficient,elastic modulus and compressive strength perpendicular-to-grain along radial direction of the wood on the seismic behavior of Dou-Gong bracket was performed.The results show that the larger the vertical load and friction coefficient,the larger the lateral stiffness and the bearing capacity of Dou-Gong bracket.However,the elastic modulus and compressive strength perpendicular-to-grain along radial direction of the wood

关 键 词：古建筑木结构 平身科斗栱 低周反复荷载试验 有限元分析 抗震性能 

分 类 号：TU366.2[建筑科学—结构工程] TU317.1TU311.41