鋼結構仿古建筑雙梁柱中節點的受力機理

戚亮杰　薛建陽　隋龍天　吳占景　許丹

摘要：為研究鋼結構仿古建筑雙梁柱中節點的抗震性能，對4個全焊雙梁柱中節點進行了水平低周反復加載試驗。通過觀測試件在側向力作用下的受力過程和破壞形態，分析雙梁柱中節點的受力機理。根據梁截面形式的不同，將其分為箱型截面梁與工字型截面梁2類，依據仿古建筑獨特的構造特點，將各試件節點核心區劃分為上、中、下3個區域。通過量測各區域內的應變大小，分析該類結構節點核心區在側向力作用下的受理機理及破壞模式，并建立雙梁柱節點的斜壓桿受力模型。試驗結果表明：仿古建筑雙梁柱節點的破壞形式主要為沿下核心區對角線的剪切破壞，并通過理論計算分析提出一種考慮軸壓比與梁截面形式的雙梁柱中節點抗剪承載力修正公式。

關鍵詞：仿古建筑；雙梁柱中節點；低周反復荷載；受力機理；抗剪承載力

中圖分類號：TU391

文獻標志碼：A文章編號：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

中國傳統古建筑具有氣勢恢宏、造型優美的特點，仿古建筑既繼承了古建筑的特點又與現代科技技術相結合，使結構的抗災害能力和耐久性得到增強[1]?，F代仿古建筑主要以鋼筋混凝土結構和鋼結構為主，改變了傳統中國古建筑以木結構為主的受力體系。目前，國內外對鋼結構梁柱節點的研究局限于常規節點和兩端梁截面形式不同或者不等高的異型節點[24]，對鋼結構仿古建筑的研究很少，尤其是對鋼結構仿古建筑框架結構雙梁柱節點的研究幾乎沒有?！?br>