Flexural and fracture performance of UHPC exposed to low-temperature environment

This manuscript experimentally studied the flexural behaviors and fracture performance of ultra -high-performance concrete (UHPC) at low-temperature environment (T = 20,-30,-60,-90,-120, and-160 degrees C). Firstly, the fundamental mechanical properties of UHPC were determined through cube tests. Then, the flexural and fracture performance of UHPC were studied through four-point bending (FPB) tests and three-point bending (TPB) notched tests, respectively. Results indicated that the mechanical properties of UHPC were improved almost linearly with decreasing temperature. The flexural tensile strength and toughness of UHPC were significantly enhanced by low temperatures. The double -K fracture toughness and energy of UHPC were remarkably improved at low-temperature environment. Empirical models of the compressive strength, splitting tensile strength, flexural tensile strength and fracture energy of UHPC at low-temperature environment were developed.