Tensile response of UHPFRC under very low strain rates and low temperatures

This paper addresses the uniaxial tensile response of Strain Hardening Ultra High-Performance Fiber Reinforced Concretes (SH-UHPFRC) subjected to very low strain rates and low temperatures. The influence of four different strain rates; 1 × 10−5, 1 × 10−7, 1 × 10−8 and 5 × 10−9 1/s on the tensile properties like elastic limit, elastic modulus, tensile strength and the strain at tensile strength, was studied for two types of SH-UHPFRC mixes; Mix I with type I cement and silica fume, and Mix II with silica fume and 50% mass replacement of type I cement with limestone filler, at three curing temperatures; 20 °C, 10 °C and 5 °C. The tests at strain rates lesser than 1×10−6 1/s are the first of their kind for UHPFRC materials and the results show a considerable impact on the elastic limit of the mixes. Acoustic Emission tests were also carried out for validation of test results of the elastic limit.