Simplified compression field theory-based model for shear strength of fabric-reinforced cementitious matrix-strengthened reinforced concrete beams

Abstract

Fabric-reinforced cementitious matrix (FRCM) systems are becoming an excellent choice for the shear strengthening of reinforced concrete (RC) beams owing to their excellent structural performance and compatibility with the concrete substrate. There is a wealth of experimental research on the application of FRCM for shear strengthening of beams; however, there is a lack of research on assessing the performance of the beams theoretically. The primary objective of this research effort, therefore, is to propose a design equation to predict the shear capacity of FRCM shear-strengthened beams. The developed equation is based on the simplified compression field theory (SCFT) combined with probability and statistical techniques. The equation can be used for calculating the shear capacity of the FRCM shear-strengthened and unstrengthened beams. The equation accounts for the contributions of concrete, longitudinal tensile reinforcement, internal shear reinforcement (ISR), and FRCM. An extensive database of shear-critical RC beams has been used to validate the developed equation. It has been found that the proposed equation can predict the shear capacity of both unstrengthened and strengthened beams with reasonable accuracy. The prediction capability of the developed equation is compared with that of the ACI 549 guideline for the strengthened beams and the ACI 318-14, AASHTO-LRDF, and Eurocode 2 (2004) for unstrengthened beams. Copyright 2020, American Concrete Institute. All rights reserved, including the making of copies unless permission is obtained from the copyright proprietors. Pertinent discussion including author's closure, if any, will be published ten months from this journal's date if the discussion is received within four months of the paper's print publication.