十字形截面型钢混凝土异形柱抗火性能分析

Fire behavior of steel reinforced concrete columns with 十-shaped cross section

建立了四周受火十字形截面型钢混凝土异形柱抗火分析有限元模型,采用钢筋混凝土异形柱试验数据验证了模型的合理性。应用验证后的模型分析了荷载比、含钢率、配筋率、偏心率、截面尺寸对型钢混凝土异形柱耐火极限的影响。分析表明,荷载比、偏心率、截面尺寸对耐火极限有较大的影响,荷载比、偏心率越大耐火极限越短,截面尺寸越大耐火极限越长;含钢率、配筋率对耐火极限的影响较小,耐火极限随含钢率的增加呈增大趋势,随配筋率的增加呈减小趋势。

A nonlinear finite element model was developed to analyze the fire resistance of steel reinforced con crete columns with 十shaped cross sections subjected to the around-face heating, which was validated by ex periment results of concrete shaped columns. Then the verified model was used to do parametric analysis on the influence of related factors such as load ratio, eccentric ratio, steel ratio, reinforcement ratio and section dimen sions on the fire resistance of the columns steel reinforced concrete columns. Results show that the load ratio, ec centric ration and section dimension have considerable influence on the fire resistance of the columns. Fire resis tance becomes shorter as the load ratio and eccentric ration increase; while the increase of the section dimension will lead to a larger fire resistance. The steel ratio and reinforcement ratio have little influence on fire resistance of columns. Fire resistance becomes larger as the steel ratio increases, and becomes a little shorter as the rein forcement ratio increases.