Flexural performance and design assessment of sustainable crumb rubber concrete beams reinforced with basalt‐
FRP
bars
Yahia M. S. Ali, Xin Wang, Zhishen Wu, Essam Jnead Abstract
Crumb rubber concrete (CRC) offers an environmentally sustainable solution for recycling waste tires through their use as a partial replacement for natural aggregates. However, limited research has investigated the structural behavior of CRC beams reinforced with basalt fiber‐reinforced polymer (BFRP) bars. This study experimentally evaluates the flexural performance of CRC beams reinforced with BFRP bars under four‐point bending. Fifteen reinforced concrete beams were tested to investigate the effects of crumb rubber (CR) replacement ratio (0%–20%), rubber particle size (5 mm and No. 20), reinforcement type (steel and BFRP), and BFRP reinforcement ratio on cracking behavior, stiffness, load‐carrying capacity, and failure mode. The results showed that increasing CR content reduced concrete density, compressive strength, flexural strength, cracking load, stiffness, and ultimate load, with the reduction becoming more pronounced when finer rubber particles were used. CRC beams exhibited more distributed cracking patterns and greater deformation capacity than conventional concrete beams. Regardless of concrete type, BFRP‐reinforced beams developed significantly higher ultimate loads than steel‐reinforced beams due to the superior tensile strength of BFRP bars. Increasing the BFRP reinforcement ratio improved cracking resistance, post‐cracking stiffness, and ultimate flexural capacity. Among the investigated mixtures, CRC containing 5% replacement of 5 mm CR exhibited the most favorable balance between sustainability and structural performance. Analytical predictions based on ACI 440.1R, CSA S806, AASHTO LRFD, Gb 50608, JSCE, SP295, and Eurocode‐based formulations showed reasonable agreement with the experimental results. The findings demonstrate the feasibility of utilizing BFRP‐reinforced CRC members as sustainable, lightweight, and corrosion‐resistant structural elements for future infrastructure applications.