Modification of strut effectiveness factor for reinforced concrete deep beams strengthened with CFRP laminates


  • M. Panjehpour University Putra Malaysia,
  • A. A. A. Ali University Putra Malaysia,
  • Y. L. Voo DURA Technology
  • F. N. Aznieta University Putra Malaysia,



Deep beam, Strut effective strength, CFRP, Shear, Strut-and-tie model


This paper proposes a method to modify the strut effectiveness factor in the strut-and-tie model for CFRP-strengthened reinforced concrete deep beams. Two groups of deep beams comprising six ordinary reinforced concrete deep beams and six CFRP-strengthened reinforced concrete deep beams were experimentally tested under the four-point bending configuration. The shear span-to-effective depth ratio of the beams in each group was 0.75, 1.00, 1.25, 1.50, 1.75, and 2.00. The theoretical principal tensile strain in CFRP-strengthened struts was modified based on a proposed empirical relationship, based on two ratios: the experimental to the theoretical value of principal tensile strain and the shear span-to-effective depth of deep beams.


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How to Cite

Panjehpour, M., Ali, A. A. A., Voo, Y. L., & Aznieta, F. N. (2014). Modification of strut effectiveness factor for reinforced concrete deep beams strengthened with CFRP laminates. Materiales De Construcción, 64(314), e016.



Research Articles