摘要
设计并研究了一种耐久性较好的混杂纤维-混凝土(HFRP-RC)组合梁.通过12根四点受弯T形梁的试验研究,分析了湿黏结等界面方式的可靠性以及HFRP-RC组合梁的性能.试验结果表明,HFRP-RC组合梁在钢筋屈服后具有明显的二次刚度,有较高的极限承载力和较好的位移延性.试验中所有使用C50混凝土组合梁的破坏模式均为梁底部纤维拉断,表明外贴FRP界面(干黏结)、直接在FRP模壳上刷胶然后浇筑混凝土界面(湿黏结)以及在FRP模壳上预黏石子形成的界面都获得了较好的黏结性能.将碳纤维(CFRP)与玄武岩纤维(BFRP)进行混杂,可以提高CFRP的极限应变值,且BFRP比例越高,提高越明显,因此计算临界混杂比和HFRP-RC组合梁极限承载力时,应考虑CFRP极限应变提高系数.
A type of hybrid fiber reinforced polymer-concrete（HFRP-RC）composite beams with high durability is designed and researched.12 pieces of 4-point bending experiments of T-shaped beams are carried out to further study the reliability of the wet-bonding and the performances of the HFRP-RC composite beams.After the yielding of the steel bars,the HFRP-RC composite beams still have secondary stiffness,high bearing capacity and good displacement ductility.The failure modes of all of the C50 beams are fiber fracture,showing that good bond behaviors can be achieved by externally bonding the FRP onto the precast concrete（referred to as dry-bond）,by applying adhesive to the FRP shuttering before the fresh concrete is cast（referred to as wet-bond）,and by coating gravel on the inside surface of the FRP shuttering before the fresh concrete is placed in position.Hybridizing the basalt fiber reinforced polymer（BFRP） with the carbon fiber reinforced polymer （CFRP） can improve the ultimate strain of the latter.And the higher the ratio of the BFRP is,the higher the ultimate strain of the CFRP is.Therefore,the improvement factor of the ultimate strain value of the CFRP should be introduced when calculating the critical mixing ratio and the theoretical capacity load values of the HFRP-RC composite beams.
出处
《东南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2010年第3期548-553,共6页
Journal of Southeast University：Natural Science Edition
基金
"十一五"国家科技支撑计划资助项目(2006BAJ03B07)
国家自然科学基金资助项目(50608015)
江苏建设系统(建筑业)科研计划资助项目(JG2007-16)
