Effect of Fiber Combinations on the Engineering Properties of High-Performance Fiber-Reinforced Cementitious Composites

摘要

Although concrete has many advantages including ease of handling, economic benefits, and high compressive strength, there are disadvantages such as low tensile strength, brittleness, and drying shrinkage. High-performance fiber-reinforced cementitious composites (HPFRCC) which has high volume of fiber reinforcement was suggested as a solution of the drawbacks of normal concrete. However, reinforcing fiber in HPFRCC may cause a decreasing workability; therefore, in this paper, optimized fiber combination with either or both metal and organic fibers is suggested to provide better performance of HPFRCC in tensile strength and ductility. Test results indicate that for a given combination of fiber, using long steel fiber, short steel fiber, and long organic fiber, decreased water-to-binder ratio (w/b) caused increased toughness and energy absorption with increased tensile strength. Additionally, increased fiber content also contributed to increased toughness; strain-hardening behaviors were observed especially, when ternary fiber content was raised to 2.0%.