PSI - Issue 54

Jamal A. Abdalla et al. / Procedia Structural Integrity 54 (2024) 609–616 Abdalla et al./ Structural Integrity Procedia 00 (2019) 000 – 000

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detected that the continuously wrapped specimens showed the most satisfying response in terms of load capacity and ductility in both NAC and RAC beams. Although the beams strengthened with inclined U-wraps showed a superior behavior compared to the beams with vertical U-wraps in the RAC group, the load-deflection response of the beams with inclined and vertical U-wraps was almost the same in the NAC group. Side-bonded beams examined the least favorable behavior among the strengthened beams.

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^ŚĞĂƌ &ŽƌĐĞ ;ŬEͿ

^ŚĞĂƌ &ŽƌĐĞ ;ŬEͿ

^ŚĞĂƌ ĨŽƌĐĞ ;ŬEͿ

Ϭ ϱ ϭϬ ϭϱ ϮϬ DŝĚƐƉĂŶ ĞĨůĞĐƚŝŽŶ ;ŵŵͿ EhͲϵϬ ZhͲϵϬ

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DŝĚƐƉĂŶ ĞĨůĞĐƚŝŽŶ ;ŵŵ Ϳ E Z

DŝĚƐƉĂŶ ĚĞĨůĞĐƚŝŽŶ ;ŵŵͿ E^ͲϵϬ Z^ͲϵϬ

(a) NC and RC

(b) NU-90 and RU-90

(c) NS-90 and RS-90

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^ŚĞĂƌ &ŽƌĐĞ ;ŬEͿ

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Ϭ ϱ ϭϬϭϱϮϬϮϱ DŝĚͲƐƉĂŶ ĚĞĨůĞĐƚŝŽŶ ;ŵŵͿ E h Z h

DŝĚƐƉĂŶ ĞĨůĞĐƚŝŽŶ ;ŵŵͿ Ehϰϱ Zhϰϱ

(d) NCU and RCU

(e) NU-45 and RU-45

Fig. 4. Comparison of load-deflection curves of NAC and RAC beams

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Z ZhͲϵϬ Z^ͲϵϬ Z h ZhͲϰϱ

E EhͲϵϬ E^ͲϵϬ E h EhͲϰϱ

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^ŚĞĂƌ ĨŽƌĐĞ ;ŬEͿ

^ŚĞĂƌ &ŽƌĐĞ ;ŬEͿ

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DŝĚƐƉĂŶ ĞĨůĞĐƚŝŽŶ ;ŵŵͿ

DŝĚͲƐƉĂŶ ĚĞĨůĞĐƚŝŽŶ ;ŵŵͿ

(a) NAC beams

(b) RAC beams

Fig. 5: Comparison of load-deflection curves of strengthening schemes

4. Conclusions This study investigated the effectiveness of strengthening shear-deficient recycled aggregate concrete (RAC) beams using carbon fiber-reinforced polymer (CFRP) laminates. The results of the four-point bending tests and analysis of shear force-deflection graphs and failure modes revealed that the shear force values obtained in NAC and RAC beams were comparable. Furthermore, the percentage increase in shear strength compared to the respective control beam was even higher for RAC beams than for NAC beams. This finding demonstrates the effectiveness of different shear strengthening configurations in enhancing the shear strength of recycled aggregate concrete beams