Effect of steel fibers and recycled concrete aggregates on the mechanical behaviour of concrete

• Published in: International journal of system assurance engineering and management Vol. 15; no. 6; pp. 2743 - 2756
• Main Authors: Mamatha, K. H., Dinesh, S. V., Shreelakshmi
• Format: Journal Article
• Language: English
• Published: New Delhi Springer India 2024; Springer Nature B.V
• Subjects: Aggregates; Compressive strength; Concrete aggregates; Concrete construction; Concrete properties; Engineering; Engineering Economics; Environmental impact; Fiber volume fraction; Flexural strength; Logistics; Marketing; Mechanical properties; Organization; Original Article; Quality Control; Recycled materials; Reinforcing steels; Reliability; Residual strength; Safety and Risk; Steel fibers; Tensile strength; Toughness; RCA; Steel fiber; Flexural toughness; Prediction models; Flexural strength; Residual strength
• ISSN: 0975-6809; 0976-4348
• DOI: 10.1007/s13198-024-02297-9

Building demolition produces construction waste in large amounts and this waste impose environmental problems. The use of recycled coarse aggregate obtained from demolished concrete will reduce environmental problems, landfill space and also saves natural aggregate sources. Though the use of recycled materials from construction is in practice, addition of recycled concrete aggregate reduces compressive strength, increases porosity and possesses poor ductile property. Addition of steel fibres can significantly improve the mechanical properties. In this study, the influence of steel fiber on the mechanical behavior of concrete made of different percentages of recycled concrete aggregate is evaluated. Water cement ratios of 0.3 and 0.4 were considered. Steel fiber volume fraction was varied from 0%, 0.5%, 0.75% and 1%. The results of compressive strength, split tensile strength, flexural strength, flexural toughness and residual strength factor are evaluated for varied percentages of recycled concrete aggregate and steel fiber contents. Results showed that with increase in steel fibers content there is improvement in compressive strength, split tensile strength, flexural strength, flexural toughness and residual strength factor of concrete made of recycled concrete aggregates. Addition of steel fiber improves the mechanical property of concrete by making it a ductile material. Natural coarse aggregates can be replaced with RCA up to 60% along with steel fibers and it is possible to achieve strength equal to that of normal concrete. The recommended optimum percentage of steel fibers is 0.75%. The models developed in this study could be used for the prediction of mechanical properties of concrete under unreinforced and fibre reinforced conditions.