Development of ultra-high-performance hybrid fiber-reinforced cement-based composites

A new ultra-high-performance hybrid fiber-reinforced cementbased composite (UHP-HFRCC) was developed in this study. The UHP-HFRCC exhibited a tensile strength of 20.1 MPa (2.9 ksi), a strain capacity of 1.06%, and energy-absorption capacity of 153 kJ/m³ (1356 lb-ft/ft³). The multi-scale fiber-reinforcement system employed herein effectively improves the mechanical properties of the UHP-HFRCCs under tension. Determining the appropriate volume fraction of the longer fibers is crucial for enhancing a variety of mechanical properties, including the tensile strength, strain capacity, and energy-absorption capacity. Besides the significant improvement in the mechanical properties of UHP-HFRCC, the cost was reduced, and the workability of the material was improved by using relatively low-volume fractions of fibers (total volume fraction = 2.5 to 3%).