碳纤维增强塑料条带约束短柱轴压性能试验

Experiment on axial compression performance of CFRP strip restraint short columns

共设计制作了两组12根混凝土短柱进行轴压试验,以约束类型、约束间距和混凝土强度等级为参数,研究了其轴压承载能力和破坏形式。结果表明:CFRP(碳纤维增强塑料)条带约束短柱与普通箍筋约束短柱的受力过程和破坏形态相似,与普通箍筋约束短柱相比,CFRP条带约束对轴压短柱拥有良好的约束效果,极限承载力均保持在较高水平;随着约束间距的减小和混凝土强度等级的增大,约束短柱的极限承载力显著提高;当采用强度等级较低的C30混凝土时,CFRP条带约束短柱的延性更理想。在此基础上,提出了CFRP条带约束混凝土强度修正系数,并推导了承载力公式,吻合度较好。

Two groups of 12 concrete short columns were designed and manufactured for axial compression test.The bearing capacity and failure mode of the columns were studied with constraint type,constraint spacing and concrete strength grade in parameters test.The experimental results show that the stress process and failure mode of the short columns confined by CFRP(carbon fiber reinforced plastic)strip are similar to those of the short columns confined by ordinary stirrups.Compared with the short columns confined by ordinary stirrups,the constraint effect of CFRP strip on the short columns under axial compression is good,and the ultimate bearing capacity is kept at a higher level.With the decrease of constraint spacing and the increase of concrete strength,the constraint is short.The ultimate bearing capacity of columns is significantly improved,and the ductility of short columns restrained by CFRP strips is better when C30 concrete with lower strength grade is used.On the basis of the test,the strength correction coefficient of CFRP strip confined concrete is put forward,and the bearing capacity formula is derived,with a good agreement.