PSI - Issue 28

Haya H. Mhanna et al. / Procedia Structural Integrity 28 (2020) 811–819 Mhanna et al. / Structural Integrity Procedia 00 (2020) 000–000

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respectively. The U-wrapped laminates and anchors were made of the same high strength carbon fiber material (V Wrap™C200H). The manufacturer specified a design thickness of the laminates to be 1.02 mm. In addition, the tensile strength, elastic modulus, and elongation at failure, as specified by the manufacturer were 1034 MPa, 73,770 MPa, and 1.4%, respectively. The laminates and anchors were impregnated and bonded to the surface of concrete by V Wrap™770 epoxy adhesive. The tensile strength, elastic modulus, and elongation at failure of the epoxy adhesive as specified by the manufacturer were 60.7 MPa, 2760 MPa, and 4.4%, respectively. 3.4. FRP anchor installation procedure After preparing the beams’ surfaces, holes were drilled at prescribed location of the anchors, while maintaining the correct hole diameter, embedment depth, and inclination angle as shown in Fig. 4. Following that, CFRP sheets were impregnated with epoxy and installed onto the beam’s surface in the form of U-wraps. Then, the CFRP anchors were fabricated manually from CFRP sheets and impregnated with epoxy. Next, the impregnated anchors were inserted into the predrilled holes and the fan was splayed onto the CFRP laminates using grooved rollers to secure a good bond with the CFRP sheets. Finally, the specimens were left to cure for 7 days before testing.

Fig. 4. FRP anchor installation.

3.5. Test setup All specimens were tested as simply supported beams under one-point loading (three-point bending) as shown in Fig. 5. An Instron Universal Testing Machine (UTM) that has a capacity of 2000 kN was used to apply a concentrated load onto a steel spreader beam at the center of the specimens, at a displacement-controlled rate of 2 mm/min. In addition, one FRP strain gauge was mounted on each of the CFRP laminates to monitor strains in the laminates as shown in Fig. 5.

Fig. 5. Test setup.