建筑專(zhuān)業(yè)畢業(yè)設(shè)計(jì)外文文獻(xiàn)及翻譯--用碳纖維板(cfrp)修復(fù)剪切不足的矩形簡(jiǎn)支梁

1、- 1 -英文原文：Rehabilitation of rectangular simply supported RC beams with shear deficiencies using CFRP compositesAhmed Khalifa a,* , Antonio Nanni ba Department of Structural Engineering, University of Alexandria, Alexandr

2、ia 21544, EgyptbDepartment of Civil Engineering, University of Missouri at Rolla, Rolla, MO 65409, USAReceived 28 April 1999; received in revised form 30 October 2001; accepted 10 January 2002 AbstractThe present study e

3、xamines the shear performance and modes of failure of rectangular simply supported reinforced concrete(RC) beams designed with shear deficiencies. These members were strengthened with externally bonded carbon fiber reinf

4、orced polymer (CFRP) sheets and evaluated in the laboratory. The experimental program consisted of twelve full-scale RC beams tested to fail in shear. The variables investigated within this program included steel stirrup

5、s, and the shear span-to-effective depth ratio, as well as amount and distribution of CFRP. The experimental results indicated that the contribution of externally bonded CFRP to the shear capacity was significant. The sh

6、ear capacity was also shown to be dependent upon the variables investigated. Test results were used to validate a shear design approach, which showed conservative and acceptable predictions. 2002 Elsevier Science Ltd.

7、○ CAll rights reserved.Keywords: Rehabilitation; Shear; Carbon fiber reinforced polymer 1. IntroductionFiber reinforced polymer (FRP) composite systems, composed of fibers embedded in a polymeric matrix, can be used for

8、shear strengthening of reinforced con-crete (RC) members [1–7]. Many existing RC beams are deficient and in need of strengthening. The shear failure of an RC beam is clearly different from its flexural failure. In shear,

9、 the beam fails suddenly without sufficient warning and diagonal shear cracks are consid-erably wider than the flexural cracks [8].The objectives of this program were to:- 3 -The mechanical properties of the materials us

10、ed for manufacturing the test specimens are listed in Table 1.Fabrication of the specimens including surface preparation and CFRP installation is described elsewhere [10].Table 12.2. Strengthening schemesOne specimen fro

11、m each series (SW3-1, SW4-1, SO3-1 and SO4-1) was left without strengthening as a control specimen, whereas eight beam specimens were strengthened with externally bonded CFRP sheets following three different schemes as i

12、llustrated in Fig. 2.In series SW3, specimen SW3-2 was strengthened with two CFRP plies having perpendicular fiber directions (90°/0°). The first ply was attached in the form of continuous U-wrap with the fiber

13、 direction oriented perpendicular to the longitudinal axis of the specimen (90°). The second ply was bonded on the two sides of the specimen with the fiber direction parallel to the beam axis（0°）.This ply [i.

14、e. 0°ply] was selected to investigate the impact of additional horizontal restraint on shear strength.In series SW4, specimen SW4-2 was strengthened with two CFRP plies having perpendicular fiber direction (90°

15、/0°) as for specimen SW3-2.Four beam specimens were strengthened in series SO3. Specimen SO3-2 was strengthened with one-ply CFRP strips in the form of U-wrap with 90°-fiber orientation. The strip width was 50