侧向冲击荷载作用下CFRP型材-方钢管混凝土柱的动力响应

Dynamic responses of CFRP profile-concrete-filled square steel tube columns under lateral impact load

为了研究CFRP型材-方钢管混凝土固简柱的抗侧向冲击性能,采用水平撞击装置对3个CFRP型材-方钢管混凝土柱进行侧向冲击试验.根据柱的破坏模式、局部变形、整体变形及冲击力分析柱的动力响应,研究了CFRP型材、边界条件、冲击能量与冲击冲量对试件动力响应的影响规律.结果表明,CFRP型材-方钢管混凝土固简柱呈现弯曲破坏,具有良好的抗冲击性能,且随着支座约束能力的增大,抗侧向冲击性能增大.增加单位冲击冲量可使悬臂试件的峰值位移下降7%,而两端固支试件峰值位移仅变化1%.随着支座约束能力的下降,冲击冲量对试件变形的影响程度增大.在钢管混凝土固简试件中内置CFRP型材可使冲击位置处峰值位移下降9%,且降低程度随着支座约束能力的下降而增加.

To investigate the lateral impact resistance of carbon fiber reinforced plastics-concrete-filled square steel tube(CFRP-CFST)columns under fixed-simply supports,the lateral impact tests of three CFRP-CFST columns were conducted using a horizontal impact test setup.According to the failure mode,local and global deformation,and the impact load of the column,the dynamic response of the column were analyzed.The influence rules of the CFRP profile,boundary condition,impact energy,and impact impulse on the dynamic responses were evaluated.The results show that the CFRP-CFST columns exhibit a bending failure mode and possess good impact resistance.The lateral impact resistance increases with the increase of the support restraint capacity.The increase of the unit impact impulse can reduce the peak displacement by 7%for cantilever specimens but only 1%for fixed specimens.The influence of the impact impulse on specimen deformation increases with the decrease of the support restraint capacity.Encasing CFRP profiles into the fixed-simply CFST specimens can reduce the peak displacement at the impact position by 9%,and the reduction increases with the decrease of the support restraint capacity.