（節(jié)選）外文翻譯英文--用frp復(fù)合材料加固的無(wú)筋紅磚墻的平面外受彎性能

1、Out-of-plane flexural behavior of unreinforced red brick walls strengthened with FRP compositesAyman S. MosallamCivil and Environmental Engineering Department, University of California, Irvine, CA 92604, USAReceived 20 M

2、arch 2006; accepted 27 July 2006 Available online 27 December 2006AbstractThis paper presents the results of a study focused on evaluating the out-of-plane flexural behavior of two fiber reinforced polymer (FRP) composit

3、e systems for strengthening unreinforced red brick masonry walls. The full-scale tests followed the International Code Council Evaluation Service (ICC-ES) AC 125 procedure. In the experimental program, a total of four fu

4、ll-scale destructive tests were conducted on UMR red brick walls. One wall specimen was used as control (as-built) specimen without composites, and the remaining three wall specimens were strengthened with either E-glass

5、/epoxy or carbon/epoxy composite systems with different fiber architecture. The effect of applying a cross-ply laminate on the ultimate failure mode has been investigated. Full-scale experimental results confirmed the ef

6、fectiveness of the FRP composite strengthening systems in upgrading the out-of-plane flexural structural performance of URM walls. In addition, an analytical model was developed to predict the ultimate load capacity of t

7、he retrofitted walls. The analytical mod- eling is based on deformation compatibility and force equilibrium using simple section analysis procedure. A good agreement between the experimental and theoretical results was o

8、btained. ? 2007 Elsevier Ltd. All rights reserved.Keywords: A. Laminates; B. Delamination; D. Mechanical testing; E. Lay-up (manual); Infrastructure1. IntroductionIn general, unreinforced masonry (URM) buildings per- for

9、m poorly in earthquakes. Two types of failure are com- monly encountered in URM buildings subjected to seismic forces. The first failure mode occurred in in-plane shear that are designed to form the lateral load resistin

10、g system of the building. The other type of failure is due to out-of- plane bending stresses caused by seismic inertial forces. The excessive out-of-plane bending is also a major reason for the loss of load carrying capa

11、city of URM walls. Fig. 1 shows a typical failure of unreinforced red brick wall due to excessive out-of-plane seismic forces. Composites offer an attractive strengthening protocol for existing and historical unreinforce

12、d masonry structures.In the past few decades, composites have successfully been used in different construction applications including strengthening of reinforced concrete, steel and timber structures. An in-depth review

13、of different applications of composites in repair and rehabilitation is discussed by Mosallam [1]. Lately, several studies have been conducted on evaluating the use of polymeric composites for repair and strengthening bo

14、th unreinforced and reinforced masonry walls subjected to seismic, wind and lateral earth pressure. The advantages of using composite materials in this application are (i) ease of application, (ii) preservation of the ge

15、ometrical and architectural details of the walls, (iii) their high strength-to-weight ratio, and (iv) their high resis- tance to corrosion as compared to metallic strengthening systems. This paper presents a summary of e

16、xperimental and theoretical results of a study that was conducted to characterize the out-of-plane flexural behavior of unrein- forced masonry walls externally strengthened with fiber reinforced polymeric (FRP) composite

17、 laminates.1359-8368/$ - see front matter ? 2007 Elsevier Ltd. All rights reserved. doi:10.1016/j.compositesb.2006.07.019E-mail address: mosallam@uci.eduwww.elsevier.com/locate/compositesbComposites: Part B 38 (2007) 559

18、–574addition, this is one of the first studies where all test procedures are confirmed with the requirements of the International Code Council-Evaluation Service (ICC-ES) Acceptance Criteria AC 125 [19].4. Experimental p

19、rogram4.1. Wall specimensA total of four unreinforced red bricks large-scale wall specimens were constructed and tested to failure. The dimensions of the walls were 2.64 m · 2.64 m (8.67 ft · 8.67 ft) and one b

20、rick wide. Large wall dimensions were selected to avoid scale effects and to reflect the actual per- formance of a weak masonry wall under out-of-plane flex- ural loading conditions. Table 1 describes the wall specimens

21、evaluated in this study. As mentioned earlier, the International Code Council-Evaluation Service (ICC- ES) Acceptance Criteria AC 125 [19] procedures were fol- lowed for all tests.4.2. MortarStandard Type-S mortar was us

22、ed in constructing these walls. The mortar was mixed to the proportion specifica- tion of ASTM C-270 Standard. The average compressive strength of the mortar was obtained by testing six 50.8 mm (200) diameter · 101.

23、6 mm (400) high cylinders taken from the same batch used in fabricating the wall specimens. The average strength ðf 0 mÞ of the mortar on the day of the tests was 21.37 MPa (3100 psi).4.3. Red bricksCommon red

24、clay bricks (Castaic) readily available from building suppliers were used. The nominal dimensions were 20.32 cm (8 in.) · 10.16 cm (4 in.) · 5.72 cm (21 4 in.). Two types of tests were conducted on the red bric

25、ks: (i) a unit brick compression test to determine the ultimate compres- sive strength (refer to Fig. 2), and (ii) a prism test (refer to Fig. 3) to determine the combined compressive strength ofTable 1 Description of wa

26、ll specimensTest ID Specimen’s descriptionControl unreinforced WCONT-U As-built wall no compositesRetrofit: carbon/epoxy WC-RET-02 2 Plies of unidirectional carbon/epoxy laminate parallel to edge supports [0?]2 WC-RET-09

27、0 1 Ply of unidirectional carbon/epoxy in each orthogonal direction (perpendicular to edge supports direction) [0?/90?]1Retrofit E-glass/epoxy WE- RET-02 3 Plies of unidirectional E-glass/epoxy laminate parallel to edge