- 摘 要
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(鄭州大學(xué)力學(xué)與安全工程學(xué)院， 鄭州 450001)
摘要: 為研究焊縫類型和內(nèi)加肋板對鋼管相貫節(jié)點超低周疲勞性能的影響，開展了 3 個 X 形方圓鋼管相貫節(jié)點的超低周疲勞試驗，研究了節(jié)點的破壞形態(tài)，分析了節(jié)點處的應(yīng)變分布規(guī)律，得到了節(jié)點的疲勞壽命。 試驗結(jié)果表明:3個 X 形方圓鋼管相貫節(jié)點的裂紋均起始于節(jié)點的鞍點位置，角焊縫和熔透焊縫 X 形方圓鋼管焊接相貫節(jié)點均呈現(xiàn)出沖切破壞特征，并且焊縫形式未對節(jié)點的變形能力和疲勞壽命產(chǎn)生明顯的影響。 主管采用的內(nèi)加勁肋的節(jié)點呈現(xiàn)出拉伸斷裂破壞特征，其變形能力較差，并且斷裂破壞前沒有明顯的表面裂紋，斷裂突然發(fā)生，因此在較高烈度的地震設(shè)防區(qū)，從節(jié)點的抗斷裂性能和變形能力考慮，在工程設(shè)計中，不建議采用主管內(nèi)加勁肋來提高節(jié)點的承載能力。
關(guān)鍵詞: 鋼管結(jié)構(gòu)； X 形方圓鋼管相貫節(jié)點； 超低周疲勞性能； 焊縫
中圖分類號:TU391 文獻標(biāo)志碼:A 文章編號:1002￣848X(2022)04￣0086￣07
DOI:10. 19701 / j.jzjg.20200280
Experimental study on ultra￣low cycle fatigue fracture of X￣shaped steel joints with circularhollow section braces to square hollow section chord
LI Xueting， HUANG Xuewei， ZHAO Jun， ZHAO Wei， GE Jianzhou， WANG Xufeng
(School of Mechanics and Safety Engineering， Zhengzhou University， Zhengzhou 450001， China)
Abstract: In order to study the effect of weld types and internal stiffening rib on ultra￣low cycle fatigue performance ofsteel tubular joints， three X￣shaped steel joints with circular hollow section (CHS) braces to square hollow section( SHS)chord were tested under ultra￣low cyclic loading and the failure modes of the joints were investigated. Meanwhile， straindistribution at the joints and fatigue life of the joints were obtained in the tests. The test results show that crack starts atthe saddle of joints for all three steel tubular joints， and punching failure is observed for the X￣shaped steel joint withCHS braces to SHS chord with fillet weld and X￣shaped steel joint with CHS braces to SHS chord with penetration weld；besides， the type of weld has no obvious influence on the deformation capacity and fatigue life of the joint. It shows tensilefracture failure characteristic for the steel tubular joint with internal stiffening rib in the chord， and the joint has verylimited deformation capacity. Furthermore， there are no obvious surface cracks before suddenly fracture failure of thejoints with internal stiffening ribs. Therefore， from the perspective of deformability and anti￣fracture performance under theearthquake action， it is not recommended to set internal stiffening ribs in steel tubes to enhance the bearing capacity ofthe joints in the seismic fortification zone with high intensity.
Keywords:steel tube structure； X￣shaped steel joints with circular hollow section braces to square hollow section chord；ultra￣low cycle fatigue performance； weld
∗國家自然科學(xué)基金項目 ( 51608487)， 河南省科技攻關(guān)項 目 ( 192102310221)， 河 南 省 高 等 學(xué) 校 重 點 科 研 項 目 計 劃(17A130002)，鄭州大學(xué)大學(xué)生創(chuàng)新創(chuàng)業(yè)訓(xùn)練計劃項目(2019cxcy338)。
第一作者:李雪婷，碩士研究生，主要從事結(jié)構(gòu)的力學(xué)性能研究，Email:1968246460@ qq.com。
[引用本文]李雪婷，黃學(xué)偉，趙軍，等.X 形方圓鋼管相貫節(jié)點超低周疲勞斷裂試驗研究[J].建筑結(jié)構(gòu)，2022，52(4):86￣92. LI Xueting， HUANG Xuewei， ZHAO Jun， et al. Experimental study on ultra￣low cycle fatigue fracture of X￣shapedsteel joints with circular hollow section braces to square hollow section chord[J]. Building Structure，2022，52(4):86￣92.
