单面受火的方中空夹层钢管混凝土短柱耐火极限

Fire resistance of concrete-filled double skin tubes stub columns exposed to fire on one face

为研究单面受火的方中空夹层钢管混凝土短柱耐火极限,在合理选择材料本构关系和边界条件的基础上,利用ABAQUS软件建立了高温下方中空夹层钢管混凝土短柱温度场和力学场分析模型,通过与试验数据对比验证,结果吻合良好。基于此模型,对不同的混凝土强度、钢管强度、内钢管厚度、空心率、荷载比进行耐火极限参数分析,并定量给出计算此类构件耐火极限的简化公式。研究结果表明:荷载比是构件耐火极限的主要影响参数。荷载比越大,构件的耐火极限越小。

This paper intends to study the fire resistance of concrete-filled double skin tubes stub columns exposed to fire on one face.The software of ABAQUS is used to establish the analysis model of the temperature and mechanical fields of such stub columns under the high temperature.Reasonable material constitutive relation and boundary condition are used.The results are in good agreement with the experimental data.Based on this model,the fire resistance limit is analyzed for various parameters,including the concrete and steel strength,inner steel tube thickness,the void ratio and the load ratio.The results show that the load ratio is the main factor affecting the fire resistance of the members.The fire resistance limit increases with the decrease of the load ratio.