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CONCRETE TECHNOLOGY58 CPI %u2013 Concrete Plant International %u2013 5 | 2025 www.cpi-worldwide.comReducing Steel, Enhancing Performance: The integration of steel fibers in precast reinforced concrete beams is a powerful tool to enhance performance while optimizing production. Bekaert%u2019s Dramix Steel Fibers, with their engineered hooked ends and optimized wire tensile strength, have been reinforcing concrete structures reliably and predictably for over 50 years. These design features ensure a safe and controlled failure mechanism, contributing to both durability and structural integrity.Figure 1 and 2 illustrate how different parameters affect the behavior and the performance of steel fiber reinforced concrete (SFRC), specifically using hooked-end fibers from the Dramix 3D, 4D, and 5D series. These fiber types differ in hook geometry, base wire strength, length, and aspect ratio (L/d), making them adaptable for a wide range of applications %u2013 from crack control to enhanced load-bearing capacity. As shown in Figure 2A, combining an improved anchoring mechanism with higher wire strength results in superior residual flexural capacity. However, the compressive strength of the concrete matrix is also critical, as it directly influences the fiber%u2019s anchorage efficiency. Designers must choose the appropriate fiber type to balance the matrix's grip on the fiber with the wire%u2019s tensile properties and elongation capacity. Figure 2B highlights the impact of fiber geometry, demonstrating that for a fixed length (e.g., L = 60 mm), a smaller diameter (i.e., a higher L/d ratio) leads to better performance, as seen with Dramix 4D fibers. Using Dramix 4D 80/60 (L = 60 mm, d = 0.75 mm) in a C32/40 concrete, Figure 2C shows that increasing the fiber dosage %u2013 i.e., the number of fibers within the control volume%u2014significantly improves performance. Finally, Figure 2D emphasizes the role of the matrix strength, reinforcing the general principle that residual flexural capacity increases with the concrete%u2019s compressive strength.A recent experimental campaign, conducted jointly by the University of Cagliari and Bekaert (Puppio, Di Giacinto, et al. %u201cPrecast steel-fiber reinforced concrete (SFRC) on beams: Results from an experimental campaign%u201d doi: 10.1016/j.engstruct.2025.120738), investigated how replacing partially conventional reinforcement with steel fibers could significantly improve the structural behavior of precast concrete elements. The results are encouraging for both designers and producers aiming to reduce rebar congestion, accelerate production, and enhance mechanical performance.Steel Fiber Reinforced Concrete (SFRC) is not new, but its adoption in load-bearing precast elements remains limited, Innovating precast concrete with steel fibers: Experimental insights into the performance and design potential of SFRC beamsNV Bekaert SA, 8550 Zwevegem, Belgiumn Danilo Di Giacinto, Global Technical & Business Development Manager, Bekaert & Falconix EngineeringFig. 1: Steel wire and hook geometry of Dramix Steel Fibers