体外预应力FRP片材加固混凝土结构的研究现状及发展

CFRP片材加固混凝土梁是一种新型的加固方法,但该方法存在着CFRP强度利用不高、对梁使用阶段性能改善不明显等问题,对CFRP施加预应力,不仅可以充分利用CFRP的强度,还能有效地改善加固梁的受力性能,进一步抑制梁的变形和裂缝的开展。体外预应力FRP片材加固混凝土结构近几年来在国外得到了广泛的研究与应用。对在该领域已有的研究成果从预应力的施工工艺、张拉控制应力、锚固措施、预应力损失和设计方法等方面进行了总结,可为今后开展相关的研究和应用提供借鉴和参考。

Status and Progress of Concrete Structures Reinforced with Externally Prestressed FRP Sheets

The new method using CFRP sheet to strengthen concrete beams has several disadvantages:the strength of CFRP sheets could not be thoroughly utilizod and the serviceability of strengthened concrete beams could not be significantly im- proved.The applied prestress in CFRP sheets could not only make full use of the strength of the CFRP sheets but also effectively enhance the forced properties of the strengthened beams,thus preventing development of the deformations and cracks.The tech- nique of concrete structures reinforced with prestressed FRP sheet has been studied widely abroad recent years.This paper pres- ents a state-of-the-art applications and researches of structure reinforced with prestressed FRP sheet.Topics include con- struction technology,pretensioned force,anchorage methods,prestressing loss and design recommendations.It provides a basis for further research and application in China.