基于有限元软件ABAQUS建立火灾后混凝土短柱推覆过程的数值分析模型,并对火灾后7根混凝土短柱的试验结果进行模拟分析,建议模型分析参数.分析水平力方向、受火时间、轴压比、剪跨比、截面尺寸、箍筋间距对三面受火后混凝土短柱受剪承载力的影响规律.基于自编的有限元程序计算三面受火后混凝土截面抗压强度的平均折减系数,提出三面受火后混凝土柱受剪承载力的实用计算方法.研究结果表明:数值模型对火灾后混凝土短柱受剪承载力的预测较准.
A numerical model for the push-over analysis of concrete short columns after fire was developed by ABAQUS, and some key finite element model parameters for the short columns were suggested through the numerical analysis of the tests of seven columns. The effects of horizontal force direction, fire exposure time, axial compressive ratio, shear span ratio, sectional dimension and stirrup spacing on the shear strength of concrete short columns after 3face heating were in vestigated based on the numerical model, The average reduction coefficient of compressive strength in concrete sections af ter 3-face heating was calculated by a self-developed finite element program, and a practical calculation method for the shear strength of concrete columns after 3-face heating was proposed. The results indicate that: the shear strength of con- crete short column after fire is well predicted by the established model.