A Mechanistic Approach to Designing Rubber–Fiber Hybrid Concrete for Structural Durability and Resilience

Abstract

The present study aims at evaluating the structural behavior of fiber-reinforced rubberized concrete, where shredded waste rubber is incorporated along with steel fibers for achieving a balance between environmental sustainability and mechanical performance. The main focus of this study is to determine how the incorporation of shredded waste rubber, along with steel fibers, would affect the mechanical properties of concrete mixes. In this study, compressive strength (fck), flexural strength (fcr), and split tensile strength (fct) are considered for evaluating the structural behavior of fiber-reinforced rubberized concrete mixes. The study involves detailed characterization of materials, optimization of mixes, and carrying out experiments to determine the mechanical properties of mixes at two different intervals: after 7 days and after 28 days. Additionally, regression analysis was carried out using three-dimensional response surfaces to determine the impact of rubber and mix grades on strength properties. The novelty of this study is the incorporation of steel fibers in rubberized concrete mixes for achieving enhanced strength properties, considering the reduction in strength due to the incorporation of rubber in concrete mixes. From this study, it was confirmed that an optimized mix of rubber and steel fibers would enhance the strength properties of mixes while maintaining satisfactory compressive strength levels. Strong statistical correlations have been observed between compressive strength, split tensile strength, and flexural strength, with an R² value greater than 0.97. From the 3D analysis, it was confirmed that compressive strength would reduce with an increase in rubber content. However, this reduction can be effectively addressed with the incorporation of steel fibers.