In-Situ Fabricated FRP Jacketing
Source:未知Author:admin Addtime:2018-02-02 15:35 Click:
Several composite jacketing systems have been developed and validated in laboratory or field conditions (Matsuda et al. 1990; Saadatmanesh et al. 1994; Seible et al. 1995; Teng et al. 2002; Xiao et al. 1996, 2000). These composite
retrofit techniques can be categorized as in-situ fabricated jacketing which involves hand or automated machine placement of epoxy saturated glass or carbon fabrics and tows on the surface of existing concrete. The key advantage of the in-situ fabricated jacket is that it can be used for most column shapes. However, due to the nature of in-situ fabrication, these systems may need special attention to the job-site quality control and curing of the FRP.
Some carbon and glass FRP retrofitting systems have been investigated experimentally (Seible et al.1997; Ma et al. 1999). In these studies, approximately one-half scale model columns were tested in either flexural or shear dominant modes. The tests have shown that FRP jacket retrofit in a flexural lap-spliced plastic hinge zone, and for full-height shear retrofit, can be just as effective as comparable steel jackets. Significantly stable hysteresis loops up to a displacement ductility level of 8 are demonstrated for flexural tests, and over 10 for shear tests. The field application and testing of carbon fiber composite jackets for three columns and cap beam of an existing concrete bridge pier were also recently carried out by Pantelides et al. (2000).
