钢骨混凝土柱的耐火性能和抗火设计方法(I)

Fire Performance and Design Method of Steel Reinforced Concrete(SRC) Columns

确定了高温下组成钢骨混凝土的钢材和混凝土的热工参数和力-热本构关系模型,利用有限元法计算了钢骨混凝土柱截面温度场,计算结果得到实验结果的验证。利用数值方法对钢骨混凝土柱耐火极限及火灾下荷载-变形关系曲线进行了计算分析,理论计算结果和实验结果吻合良好。在此基础上,分析了截面尺寸、构件长细比、截面含钢率、截面配筋率、荷载偏心率、钢骨和钢筋屈服强度、混凝土强度、截面高宽比等参数对耐火极限以及火灾下构件承载力的影响规律。最后,提出了钢骨混凝土柱耐火极限的实用计算公式。本文是第一部分。

The thermal properties and the stress-strain relations of steel and concrete in steel reinforced concrete （SRC） columns under high temperature are determined. Finite element method is applied to calculate the temperature fields of the sections. A comparison between calculated results and tested results of temperatures shows good agreement. A numerical method is developed to calculate the fire resistance and the load-deformation curves of steel reinforced concrete columns. The calculated results agree well with those of tests. Based on the theoretical model,influences of the parameters,such as sectional dimensions, slenderness ratio, steel ratio, reinforcement ratio, load eccentricity ratio, strength of steel section and reinforcement ,strength of concrete and length-to-width ratio of the section on fire resistance and bearing capacity under fire are analyzed. A simplified model is developed for calculating the fire resistance of steel reinforced concrete columns. This is the first part of the article.