方套方形钢管混凝土叠合柱单面受火下的力学性能分析  

Study on mechanical performance of square steel tube⁃reinforced concrete(ST⁃RC)columns subjected to one⁃side fire

作　　者：杨力 包延红 Yang Li;Bao Yanhong(School of Civil Engineering,Qinghai University,Xining 810016,China)

机构地区：[1]青海大学土木工程学院,青海西宁810016

出　　处：《建筑科学》2023年第5期43-53,共11页Building Science

基　　金：青海省自然科学基金资助项目(2019⁃ZJ⁃971Q)。

摘　　要：为研究方套方形钢管混凝土叠合柱单面受火下的力学性能,利用有限元分析软件ABAQUS建立其单面受火下的数值模型,分析此类叠合柱单面受火下的截面温度场分布、耐火极限、破坏模式、内力重分布、耐火极限影响因素。研究发现,基于单面受火下的方套方形钢管混凝土叠合柱温度场于横截面呈单轴对称分布,偏心荷载、热膨胀附加偏心以及材料强度偏心三者之间相互作用对其耐火性能具有一定影响,荷载比、柱截面尺寸、长细比、截面核心面积比、荷载偏心率、外部混凝土抗压强度对其耐火极限具有显著影响;给出了方套方形钢管混凝土叠合柱单面受火下的耐火极限简化计算公式,为实际工程中评估此类构件的抗火设计提供有效可行的计算方法。In order to study the mechanical properties of square steel tube⁃reinforced concrete(ST⁃RC)columns under one⁃side fire,the finite element analysis software ABAQUS is used to establish the numerical model of square ST⁃RC columns under one⁃side fire.The distribution of temperature field,fire resistance,failure mode,redistribution of internal force and influence factors of fire resistance of this kind of composite column are studied.It is found that the temperature field of square ST⁃RC column under one⁃side fire is uniaxial symmetric in cross section,and the interaction of eccentric load,additional thermal expansion eccentric and material strength eccentricity has certain influence on its fire resistance.Load ratio,sectional dimension,slenderness ratio,sectional core area ratio,load eccentricity ratio and external concrete compressive strength have significant influence on its fire resistance.A simplified formula for calculating the fire resistance of square ST⁃RC column under one⁃side fire is given,which provides an effective and feasible calculation method for evaluating the fire resistance design of such structural member in practical engineering.

关 键 词：方套方形钢管混凝土叠合柱 单面受火 力学性能 耐火极限 简化计算公式 

分 类 号：TU398[建筑科学—结构工程]