CFRP约束有预载矩形SRC短柱轴压性能有限元分析

Finite element analysis of axial compressive behavior of CFRP-confined preloaded steel reinforced concrete rectangular short column

为了研究预载水平对碳纤维增强聚合物(carbon fiber reinforced polymer,CFRP,又称为"碳纤维布")约束型钢混凝土(steel reinforced concrete,SRC)矩形短柱轴压性能的影响,文章采用有限元软件对已有试验试件进行了数值模拟,结果表明采用混凝土损伤塑性模型可较好地模拟预载后加固型钢混凝土柱在有材料损伤后的力学性能。通过数值分析发现,碳纤维布对型钢混凝土矩形短柱的约束作用主要集中在水平截面的柱角部和靠近型钢部位;预载水平提高后,峰值荷载下试件中混凝土的竖向应力降低,且远离型钢部位的柱角部混凝土应力变化最明显,同时预载水平对碳纤维布工作应变有影响;建立了预载水平与碳纤维布有效拉应变的关系式。

To analyze the effect of preload level on the behavior of carbon fiber reinforced polymer （CFRP）-confined steel reinforced concrete（SRC） rectangular short columns under concentric compres- sion, the compressive behavior of the specimens designed in the experiments was simulated by the fi- nite element metho＆ It was found that the concrete damaged plasticity model could predict the me- chanical properties of the rehabilitated preloaded SRC columns at a reasonable degree of accuracy. The effects of confinement offered by CFRP mainly focused on the corner zones of columns and the zone near steel. The vertical stress of concrete in columns decreased with the increase of the preload level under the peak load, in which the corner zones decreased most obviously. Meanwhile, the preload level also influenced the circumferential strain of CFRP. Based on the previous researches, the relationship between the preload level and the effective circumferential strain of CFRP was proposed.