Introduction to Steel Fiber Recycled Aggregate Concrete.Steel fibers, typically made from high-strength steel, are dispersed throughout the concrete matrix, providing reinforcement and improving the structural performance of the material.Among these materials, steel fiber recycled aggregate concrete (SF-RAC) has emerged as a promising solution, offering a combination of environmental benefits and structural performance.SF-RAC represents a significant evolution in concrete technology, integrating two key elements: recycled aggregates and steel fibers.