Numerical simulation of ultra-high-performance fiber-reinforced concrete frame structure under fire action

The research activity in progress and the advancements in concrete technology are leading to an increased use of ultra-high-performance fiber-reinforced concrete (UHPFRC) in structural engineering. UHPFRC is characterized by steel fibers, cement, silica fume, fine sand, superplasticizer, and very low water–cement ratio. UHPFRC is defined as a new material, with unique properties (high ductility, low permeability, very high strength capacity in compression, higher toughness) in comparison with conventional concrete (Buttignol et al, Revista IBRACON de Estruturas e Materiais 10(4):957–971, 2017). This makes it possible to make slender constructions because a smaller cross section can transfer the same force as a larger cross section. However, in case of fire safety design a disadvantageous behavior of UHPC compared to normal-strength concrete is well known and documented. The high packing density of the cement matrix is the main reason for explosive spalling behavior when exposed to fire. In this paper, the numerical simulation using finite-element method has been used to evaluate the behavior of UHPFRC frame structure under fire action. According to results, the three-dimensional finite-element model can be used for calculating the mechanical localized of UHPFRC concrete frame structures subjected to nominal fire curves. The results of numerical analysis under fire action are also compared to the other materials for more understanding the fire resistance between UHPFRC material (with PP fiber, without PP fiber) and high-strength concrete. © 2020, Springer Nature Switzerland AG.