钢结构仿古建筑双梁柱中节点的受力机理

戚亮杰　薛建阳　隋龙天　吴占景　许丹

摘要：为研究钢结构仿古建筑双梁柱中节点的抗震性能，对4个全焊双梁柱中节点进行了水平低周反复加载试验。通过观测试件在侧向力作用下的受力过程和破坏形态，分析双梁柱中节点的受力机理。根据梁截面形式的不同，将其分为箱型截面梁与工字型截面梁2类，依据仿古建筑独特的构造特点，将各试件节点核心区划分为上、中、下3个区域。通过量测各区域内的应变大小，分析该类结构节点核心区在侧向力作用下的受理机理及破坏模式，并建立双梁柱节点的斜压杆受力模型。试验结果表明：仿古建筑双梁柱节点的破坏形式主要为沿下核心区对角线的剪切破坏，并通过理论计算分析提出一种考虑轴压比与梁截面形式的双梁柱中节点抗剪承载力修正公式。

关键词：仿古建筑；双梁柱中节点；低周反复荷载；受力机理；抗剪承载力

中图分类号：TU391

文献标志码：A文章编号：16744764（2016）01001706

Abstract：

We carried out horizontal low cyclic loading tests of four allwelded double beamcolumn inner joints to study the seismic performance of the double beamcolumn inner joints of the steel intimated ancient building. We studied the mechanical performance of the double beamcolumn inner joints

according to the loading process and failure pattern of the specimens under the action of lateral forces， and divided the double beamcolumns into two kinds，which were the box section beam and Ishaped section beam，

according to different section forms of beam. On the basis of the Based on unique structural features of the intimated ancient building，we divided the joint core area of each specimen into three regions，which were upper core zone， middle core zone and lower core zone. By measuring the shear strain within the scope of every area，we analyzed the mechanism performance and failure modes of the joints under lateral forces， and established the diagonal strut mechanism. The experimental results and theoretical analysis show that the failure mode of the double beamcolumn joints of the intimated ancient building is mainly for the shear failure along the diagonal of the lower core area. So we presented a modified formula of shear bearing capacity of double beamcolumn inner joints considering the axial compression ratio and the cross section of the beams.

Keywords：imitated ancient building； double beamcolumn inner joints； low cyclic loading； mechanical performance； shear capacity

中国传统古建筑具有气势恢宏、造型优美的特点，仿古建筑既继承了古建筑的特点又与现代科技技术相结合，使结构的抗灾害能力和耐久性得到增强[1]。现代仿古建筑主要以钢筋混凝土结构和钢结构为主，改变了传统中国古建筑以木结构为主的受力体系。目前，国内外对钢结构梁柱节点的研究局限于常规节点和两端梁截面形式不同或者不等高的异型节点[24]，对钢结构仿古建筑的研究很少，尤其是对钢结构仿古建筑框架结构双梁柱节点的研究几乎没有。……