Enhancing the Ductility of a Reinforced Concrete Beam using Engineered Cementitious Composite

Abstract

A series of small-scale rectangular reinforced concrete beams made with different mix proportions were presented. The beams were fabricated using normal concrete designated as specimen control (NC), normal concrete blended with supplementary material using Class F fly ash (SMFA), and engineered cementitious composite (ECC). The beams comprised of similar reinforcement where the ratio of compression, tension, and transverse bars were 1.0%, 1.5%, and 1.0% respectively. To this end, the beams were tested under four-point bending and they were intended to fail in flexure mode. The tests also aimed to provide direct evidence regarding the improvement of beam ductility due to the use of ECC. Furthermore, the performance of test beams on the overall strength, crack pattern, and damage state was also assessed. To corroborate the experimental work, an analytical work employing nonlinear finite element analysis using Abaqus was also included. From this study, it was found that each beam demonstrated a discernible ductile plateau upon the post-cracking region with Beam ECC showing the largest ductility compared to the other two thereby suggesting that the use of ECC could enhance the beam ductility. It was also shown that the flexural cracks manifested in Beam ECC were less critical, signifying that ECC is a damage-tolerant composite. Furthermore, the overall results of predicted load-deflection and damage state obtained from Abaqus were also in a good agreement with the experimental results.