L型钢管混凝土芯柱耐火极限研究

火灾高温对结构安全有显著影响,为研究等肢L形钢管混凝土芯柱的耐火极限及其影响因素,利用ABAQUS软件建立合理的高温反应分析模型,在验证模型可靠性基础上,分析了荷载比、截面边长、长细比、荷载偏心率、含钢率等对L形钢管混凝土芯柱耐火极限的影响。研究结果表明:在一定参数范围内,荷载比和截面边长是构件耐火极限的主要影响参数,荷载比越小,截面边长越大,构件的耐火极限越高;长细比和荷载偏心率对其影响较大,长细比和荷载偏心率越小,构件的耐火极限越高;含钢率对其影响不显著。结果可为异形钢管混凝土芯柱的抗火安全设计提供参考。

Fire resistance of concrete-filled steel tube core column of L-shaped cross section

In view of the fact that fire and high temperature have a significant effect on structural safety, the paper aims to study fire resistance and the influencing factors of concrete-filled steel tube core of L-shaped cross section. High temperature reaction analysis model is established by the finite element analysis of ABAQUS. Based on the verification of model reliability, the impact of load ratio, sectional width, slenderness ratio, load eccentricity and steel ratio on the fire resistance of L-shaped steel concrete core columns is analyzed. Within a certain range of parameters, load ratio and cross-sectional dimensions are the major parameters influencing the fire resistance of the main components. Smaller load ratio and larger cross-sectional dimension lead to higher fire resistance of components. Slenderness ratio and load eccentricity have high impact on the fire resistance, while steel ratio has negligible effect.