Proposition of parametric data for UHPC at high temperatures

Abstract

Ultra-high-performance concrete (UHPC) has exceptional mechanical properties at room temperature. However, its fire behavior is not well known. There are no standardized procedures for characterizing UHPC at high temperatures. This is due to the lack of research on the subject and leaves gaps for experimental and numerical investigations. This study collects a set of parametric data of UHPC at high temperatures. Thermal diffusivity, thermal conductivity and specific heat as thermal parameters, compressive strength and elastic modulus as mechanical and thermal strain and density as physical parameters were defined for different temperature ranges. The results were compared with other structural concretes (NSC, HSC and UHSC) proposed in the literature. The UHPC exhibited a particular fire behavior. Compared to NSC, HSC and UHSC, the thermal expansion and mechanical parameters of UHPC are less affected in fire, but its thermal conductivity and mass loss are higher. UHPC also has the highest specific heat compared to other concretes. When compared to the others, UHPC has a higher thermal field. A FEA-numerical analysis was made using Abaqus software to compare the thermal fields of UHPC and NSC cross-sections in order to demonstrate and apply the equations supplied in this research.