Recent efforts on investigating the effects of recycled rubber content on the mechanical properties of structural concrete

Abstract

Rubberized concrete effectively prevents brittle failures and enhances the ductility and energy absorption of concrete. It has been observed that the inclusion of rubber reduces the strength and abrasion resistance of concrete; however, the enhancement in energy absorption is significant. A vast number of tires end up as waste, posing a major environmental issue globally. The disposal of waste tires has become an acute environmental challenge, with billions discarded and buried worldwide, representing a significant ecological threat. Consequently, utilizing rubber in the concrete industry can be advantageous for both the environment and the industry. This study presents an extensive review of the effects of various rubber contents on the mechanical properties of concrete. The scope of the review encompasses an analysis of a diverse range of studies conducted over the past decade, focusing on the influence of rubber content on concrete's mechanical performance. The analysis revealed that the optimal amount of rubber to be used in concrete is in the range of 2–5% as a replacement for natural concrete aggregate. Furthermore, replacing aggregate with treated rubber may offer additional benefits, including improved energy absorption and sustainability. However, despite the promising benefits of rubberized concrete, there is a notable gap in the literature regarding the creep behavior of rubberized concrete, a crucial parameter for defining concrete performance, particularly in superstructures. This gap underscores the need for further research to comprehensively understand the long-term behavior of rubberized concrete under sustained loading conditions. Additionally, while coating or treating rubber could mitigate the reduction in mechanical properties associated with rubber inclusion, there remains a need for more investigation into the brittleness index and energy absorption of treated rubber. Addressing these gaps in knowledge will contribute to a more thorough understanding of the potential applications and limitations of rubberized concrete in various engineering contexts.