为了揭示钢筋/混凝土相对高温强度的随机性对柱耐火极限的影响,根据钢筋/混凝土相对高温强度随温度变化的均值曲线计算柱耐火极限.计算结果表明:随着荷载偏心率的增加,钢筋相对屈服强度随温度变化的随机性对柱耐火极限的影响不断增强,致使柱耐火极限变异系数总体上逐渐增大,大致从0.003左右增长至约0.060;而混凝土相对高温强度随温度变化的随机性对柱耐火极限的影响却不断减弱,但其引发的柱耐火极限变异系数波动不大,平均约0.050左右;柱耐火极限服从正态分布.
In order to reveal the influence of random characteristics of the relative steel bar/concrete strength on the fire resistance of column at a high temperature,the fire resistance of column is calculated according to the average curve of the relative strength versus the temperature.The results show that,with the increase in the eccentricity ratio of load,the effect of the random characteristics of the relative yield strength of steel bar at a high temperature on the fire resistance of column continuously improves and the variance coefficient of the fire resistance of column gradually increases from 0. 003 to about 0. 060, that, though the influence of the random characteristics of relative strength of concrete at a high temperature continuously decreases, the variance coefficient of the fire resistance of column averages out at about 0. 050, and that the fire resistance of column distributes in a normal mode.