Axial compressive behavior of GFRP-timber-reinforced concrete composite columns

This paper investigated the compressive behavior of a novel glass fiber reinforced polymer(GFRP)-timber-reinforced concrete composite column(GTRC column),which consisted of reinforced concrete with an outer GFRP laminate and a paulownia timber core.The axial compression tests were performed on 13 specimens to validate the effects of various timber core diameters,slenderness ratios,and GFRP laminate layers/angles on the mechanical behaviors.Test results indicated that with the increase in the timber core diameter,the ductility and energy dissipation ability of the composite column increased by 52.6%and 21.6%,respectively,whereas the ultimate load-bearing capacity and initial stiffness showed a slight decrease.In addition,the GFRP laminate considerably improved the ultimate load-bearing capacity,stiffness,ductility and energy dissipation capability by 212.1%,26.6%,64.3%and 3820%,accordingly.Moreover,considering the influence of timber core diameter,an ultimate load-bearing capacity adjustment coefficient was proposed.Finally,a formula was established based on the force equilibrium and superposition for predicting the axial bearing capacity of the GTRC columns.

本文提出了一种由外层玻璃纤维增强复合材料(GFRP)布、内部填充泡桐木芯和钢筋混凝土组成的组合柱(GTRC柱)。对13个GTRC柱试件进行了轴心受压试验,研究了不同木芯直径、长细比和GFRP层数/铺层角度对其力学性能的影响规律。结果表明,随着木芯直径的增加,组合柱的延性和耗能能力分别增加了52.6%和21.6%,而极限承载力和初始刚度略有下降。另外,GFRP布显著提高了其极限受压承载能力、刚度、延性和能量耗散能力,分别提高了212.1%、26.6%、64.3%和3820%。此外,考虑到木芯直径的影响,提出了极限受压承载力调整系数。最后,基于力平衡原理和叠加原理,建立了GTRC柱极限承载力理论分析模型,得到了其承载力计算公式。