Mechanical properties and ductility behavior of ultra-high performance fiber reinforced concretes: Effect of low water-to-binder ratios and micro glass fibers

Abstract

This experimental work investigates the mechanical performance and ductility behavior of Ultra-High Performance Fiber Reinforced Concrete (UHPFRC) containing high volume of micro-glass fibers (MGF). The influence of various volume fractions of MGF and two water-to-binder ratios (w/b) are investigated. These w/b ratios are 0.12 and 0.14. Based on these ratios, two groups of UHPFRC mixes were prepared and each group include seven mixes made with 0%, 0.5%, 1%, 1.5%, 2%, 2.5%, and 3% MGF volume dosages. In total fourteen mixes were examined for the mechanical properties such as compressive strength, splitting tensile strength, modulus of elasticity, flexural strength; and the ductility behavior. It was concluded that lower w/b resulted in better mechanical performance. Also, the mixes containing 1.5% to 3% of MGF, resulted in the highest compressive strength reaching up to 160 MPa. Furthermore, the results indicated that no more strength enhancement can be achieved beyond 1.5% MGF.