CFRP加固对拱形拱腹混凝土桥梁性能的影响

INFLUENCE OF CFRP STRENGTHENING ON THE BEHAVIOR OF CONCAVELY-CURVED SOFFIT CONCRETE BRIDGE GIRDERS

在过去的几十年里,纤维增强聚合物(FRP)越来越多地应用于不同的混凝土结构构件加固中。本工程的主要目的是研究曲率对用碳纤维增强聚合物(CFRP)加固的拱形拱腹钢筋混凝土(RC)桥梁性能的影响。本试验方案旨在评估凹度和拱腹曲率对碳纤维布层合板利用率和承载能力的影响,并与采用相同碳纤维加固的平拱腹钢筋混凝土梁进行比较。据此,对跨度2 m以上、具有相同拱腹曲率(20 mm/m)、长度2.7 m的5根梁进行三点单调静力加载试验,直至破坏,其中CFRP预制层合板用于外部抗弯加固。结果表明,20 mm/m的曲率使加固后的弯梁承载能力下降15.9%~17.8%。

Over the last few decades,fiber reinforced polymer(FRP)has been increasingly used in strengthening different structural concrete members.The main objective of this research is to study the influence of curvature on the performance of curved soffit reinforced concrete(RC)bridge girders that have been strengthened with carbon fiber reinforced polymers(CFRP).This experimental program was designed to evaluate the effect of concavity and soffit curvature on the CFRP laminate utilization and load capacity,compared to flat soffit RC beams strengthened with the same CFRP system.Accordingly,five beams,2.7 min length and having the same degree of soffit curvature(20 mm per 1 meter)extending over 2 meters of the span length,were tested under three-point monotonic static loading up to failure.CFRP pre-cured laminates were used for external strengthening in flexure.It was observed that 20 mm/m degree of curvature reduced the load-carrying capacity of strengthened concavely curved RC beams by 15.9%~17.8%.