Issue 63

M. Khalaf et alii, Frattura ed Integrità Strutturale, 63 (2023) 206-233; DOI: 10.3221/IGF-ESIS.63.17

experimentally. Both numerical and experimental mode of failure is shear due to excessive local shear deformation within the opening region especially at opening lower left and upper right corners as shown in Fig. 8-b. For the strengthened rectangular opening model shown in Fig. 9-a; the results convergence is noticed up to Pcr of 17.72kN which is 11.4% less than the experimental Pcr which records 20kN. Regarding the ultimate failure load, the numerically recorded value is 2.7% more than that recorded experimentally. The numerical recorded deflection at the mid span is 9.8mm which is higher than 8.35mm that recorded experimentally. This proved an over determination of about 17.37%. Due to CFRP sheets existence, the cracking patterns is not clear in the experimental images as shown in Fig. 9-b.

Experimental model i t l l

(a) Load-mid span deflection curve. (b) Cracking pattern. Figure 7: Experimental versus proposed numerical modeling technique results for the control solid RC beam without opening.

Experimental model

( a ) Load- mid span deflection curve. ( b ) Cracking pattern. Figure 8: Experimental versus proposed numerical modeling technique results for the RC beam with un-strengthened rectangular opening.

Experimental model - face

Experimental model - back

( a ) Load-mid span deflection curve. ( b ) Cracking pattern. Figure 9: Experimental versus proposed numerical modeling technique results for the RC beam with strengthened rectangular opening.

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