干湿交替与荷载作用下CFRP加固混凝土梁的耐久性_英文_李杉.pdf

Journal of SoutheastUn iversity (English Edition) Vol. 25, No. 3, pp. 37 - 380 Sept. 2009 ISSN 1003 7985 Durability of concrete beam s reinforced w ith CFRP sheet under w et-dry cycles and loading L i Shan Ren Hu itao Huang Chengkui Cu iY unfei ( S tateK ey Laboratory of C oastal and O ffshore Engineering, Dalian Un iversity of Technology, D alian 11 024, C hina) Ab stract: The test resultso f eight concrete beam s reinforced w ith crease in curvature and deflection. In add ition, wet-dry cond-i carbon f iber reinforced polymer (CFRP ) sheets subjected to an tions can lead to degradation of the bond betw een CFRP and aggressive env ironment under a sustained load are presented. The concrete through w ater absorption by the epoxy[8-10] . Thus, it is beam s are 1700mm long w ith a rectangular cro ss-section of 120- essential to investigate the overall response of the RC beam s mm w idth and 200-mm depth. The beam s are precracked w ith a externally strengthened w ith CFRP sheets exposed to the con- four-point flexural load, bonded CFRP sheets, and placed into ditions under sustained loads. In this paper, the responses of w et-dry salinewater(N aC l) either in an unstressed state or loaded RC beam s strengthened w ith CFRP sheets subjected to w et- to about 30% or 0% of the initial ultmi ate load. The indiv idual dry conditions under sustained loads are presented. and coupled effects ofw et-dry salinew ater and sustained bending stresses on the long term behaviour of concrete beam s reinforced 1 Expermi ental P rogram w ith the CFRP are investigated. The test results show that the There are wt o aspects in th is paper. They are the influence coupled action of w e-t dry saline w ater and