古建糟朽叠合梁受弯性能数值模拟研究  

Simulation on Bending Performances of Ancient Superposition Beam with Decay Components

作　　者：周乾[1,2] 

机构地区：[1]故宫博物院,北京100009 [2]北京工业大学工程抗震与结构诊治北京市重点实验室,北京100124

出　　处：《水利与建筑工程学报》2012年第3期20-24,51,共6页Journal of Water Resources and Architectural Engineering

基　　金：故宫博物院科研基金(KT2007-4);文化部科技创新项目(17-2009)

摘　　要：勘查发现,故宫英华殿某檩三件(檩、垫板、枋组成的叠合梁)存在糟朽问题。为有效保护该檩三件叠合梁,采取数值模拟研究方法,研究了其糟朽后的弯曲受力性能。根据檩、枋构件的糟朽现状,建立了剩余构件的有限元模型,并考虑叠合梁边界条件为榫卯连接。通过静力分析,获得了檩、枋糟朽条件下檩三件剩余部分的内力和变形,评价了其抗弯性能,提出了可行性加固方案。结果表明:檩、枋糟朽一定的尺寸后,檩三件叠合梁剩余部分仍能满足变形及抗弯承载力要求。此外,枋剩余截面仍能满足抗剪承载力要求,檩则因剩余截面尺寸过小而导致抗剪承载力不足。因此,对于檩和枋,应采取不同的加固措施,以减小叠合梁的破坏。It was found by survey that the decay occured on a superposition beam（composed of purlin,tie plate and tie beam） of Yinghua Palace in the Forbidden City.To effectively protect the decayed superposition beam,its bending performances were studied by simulation.Based on the decay status of purlin and tie beam parts,the finite element model of remain parts of the superposition beam was built considering the tenon-mortise connection type of boundary conditions.By static analysis,the displacement,bending as well as shear strength of the decayed superposition beam under vertical loads were obtained,and the feasible suggestions for strengthening were proposed.The results show that the decayed superposition beam still has enough bending strength,and its maximum displacement value is still within permission scope.Besides,so far as shearing strength,the remain part of tie beam is still strong enough,while the remain purlin is not so strong because of its insufficiency section sizes.Thus the different strengthening methods have to be considered and adopted for the decayed purlin and tie beam to mitigate the destruction of the superposition beam.

关 键 词：古建筑木结构 叠合梁 糟朽 抗弯性能 数值模拟 

分 类 号：TU366.2[建筑科学—结构工程]