CFRP加固高强混凝土梁锚固方式试验研究  

Experimental Study on Anchorage Methods of Reinforced High-strength Concrete Beams Repaired by CFRP

作　　者：王苏岩[1] 梁金永[2] 王泽源[1] 

机构地区：[1]大连理工大学,辽宁大连116024 [2]中国汽车工业工程公司,天津300190

出　　处：《防灾减灾工程学报》2012年第6期678-685,共8页Journal of Disaster Prevention and Mitigation Engineering

基　　金：国家自然科学基金项目(50878035)资助

摘　　要：高强混凝土梁受拉底面粘贴补强纤维布后,延性降低显著。为提高补强梁的综合性能,利用四点弯曲梁静载试验,在补强加固梁梁端及跨中实施不同的锚固方式,对比不同锚固组合下加固梁的强度和延性。研究表明:端部U锚能改善加固梁破坏模式,提高加固梁的延性和强度及补强纤维布的利用率。端部U锚联合跨中全包锚固能进一步提高加固梁的延性,显著提高补强纤维布的利用率,且能平衡变形性和承载力在安全储备中的比重;在补强纤维布断裂后,能有效限制补强纤维布的剥离和滑移,继续发挥补强作用,使加固梁延性和强度得以恢复;能对包裹区混凝土产生约束作用,提高混凝土的延性。因此端部U锚联合跨中全包锚固是合理且有充分安全储备的锚固方式。The ductility of the high strength RC concrete beam would diminish significantly if the CFRP is attached to the bottom of the beam.Thus,in order to improve the whole performance of beams strengthened by CFRP,different anchorage methods at beam ends and mid-span are applied to the flexure strengthened beams;and then the mechanical characteristics achieved by four-point bending static loading test are compared.Study shows that U-shaped end anchorages can change the failure mode of flexure strengthened beams;also enhance the flexure capacity,ductility and the utilization ratio of reinforcing CFRP.The U-shaped end anchorages,together with fully CFRP-wrapped mid-span anchorages,could further improve the ductility of test beams,notably increase the utilization ratio of reinforcing CFRP,and balance the proportion of deformability and flexure capacity at a fixed safety reservation.Moreover,they also could decrease the occurrence of sheet＇s stripping and sliding after reinforcing FRP fractures.Therefore,the load capacity and ductility could recover,while the CFRP fully wrapping at the mid-span can bring about confined concrete effect,improving the ductility of concrete.Consequently,the U-shaped end anchorages,along with fully CFRP-wrapped mid-span anchorages,belong to the rational anchorage method with enough safety reservation.

关 键 词：碳纤维布(CFRP) 高强混凝土梁 U型锚固方式 抗弯补强加固 

分 类 号：TU375.1[建筑科学—结构工程]