外包钢筋混凝土加固撞击后格构式钢柱轴压力学性能研究  

Research on axial compression performance of impacted built-up battened steel columns strengthened by outsourcing reinforced concrete

作　　者：白铁峰 Bai Tie-feng(China Railway Construction Group Corporation Limited,Beijing 100040,China)

机构地区：[1]中铁建设集团有限公司,北京100040

出　　处：《工程抗震与加固改造》2023年第6期160-168,共9页Earthquake Resistant Engineering and Retrofitting

摘　　要：格构式钢柱具有截面开展、承载力高等特点,在工业厂房中应用广泛,但其在服役过程易遭受撞击作用导致承载力不足,因此有必要对其进行撞击后损伤评估与改造加固。基于上述背景,首先,本文对8根外包钢筋混凝土(RC)加固柱进行了轴压试验,分析了其加载全过程的受力机理与破坏模式;其次,基于ABAQUS建立了RC加固柱的有限元模型,重点研究了撞击损伤与材料强度对外包RC加固柱极限承载力的影响,并基于试验与有限元结果提出外包RC加固柱的承载力计算公式。研究结果表明:撞击损伤造成轴压过程中试件受力不均,钢柱受撞侧混凝土顶部首先出现裂缝,随后裂缝扩展,最终柱中混凝土被压碎。对于不同损伤程度的格构式钢柱,外包钢筋混凝土均可改善其承载力,且随着混凝土强度增大其增强效果越明显。Built-up battened steel columns have been widely used in industrial plant due to the advantages of open cross-section and high bearing capacity.However,they are vulnerable to the impact loading during their service life.Therefore,it is necessary to carry out damage assessment and strengthen after an impact loading.Based on the above background,a total of 8 impacted built-up battened steel columns strengthened by outsourcing reinforced concrete(RC)are tested,and the mechanical mechanism during the whole loading process is analyzed.Additionally,the finite element(FE)models of the RC column are established using ABAQUS software.The influence of impact damage and material strength on the ultimate bearing capacity of the RC strengthened columns is studied.On the basis of experimental and FE results,the formula of bearing capacity of RC strengthened column is established.The results show that due to the damage induced by the impact,the strengthened columns exhibit non-uniform stress distribution across the crosssection.The concrete cracks first appear on the top of the specimens at the impact side,and then the cracks spread at the mid-height until the crush.For the built-up battened steel columns with different damage degree,the load bearing capacity is improved by the outsourcing reinforced concrete,and the strengthen effect becomes obvious when the concrete strength increases.

关 键 词：外包钢筋混凝土加固 撞击损伤 格构式钢柱 轴压 有限元 

分 类 号：TU391[建筑科学—结构工程]