约束高强度Q460钢柱抗火性能分析

Fire Resistance Analysis of Restrained High Strength Q460 Steel Columns

为了研究高强度约束钢柱在火灾下的反应,根据高强度结构钢Q460在高温下的力学性能参数,建立了约束高强度钢柱受火分析模型,得到了高强度约束钢柱在火灾下的轴向位移、跨中挠度、最大应力以及临界温度。采用有限元分析对理论结果进行了验证,两者吻合很好。利用验证过的该文计算方法计算了2种荷栽比、长细比和约束刚度比条件下的高强钢柱的抗火性能;采用CECS200:2006的力学性能参数计算了约束普通钢柱的抗火性能。通过对高强钢和普通钢的抗火性能分析发现,轴向约束明显降低钢柱的临界温度,长细比、荷载比越大,临界温度越低;高强钢的抗火性能要优于普通钢。

In order to investigate the behavior of high strength steel column in fire,the analysis model is established based on mechanical properties of Q460 at high temperatures.The axial displacement,midspan deflection,maximum stress and critical temperature for high strength steel columns are obtained. The analysis results are validated by finite element analysis,and a good agreement is found.The fire resistance of high strength steel columns,which have two kinds of load ratio,slenderness ratio and axial restraint stiffness,is calculated by the validated calculation method.The fire resistance of conventional steel columns is also calculated based on mechanical properties of CECE200：2006.Through the comparison of the fire resistance of high strength steel columns with that of conventional steel columns,it is found that axial restrain reduces the critical temperature of steel column significantly;the critical temperature decreases with the increase of slenderness ratio and load ratio;And the fire resistance property of high strength restrained steel columns is better than conventional steel columns.