Numerical modeling of steel fiber reinforced concrete spallation exposed to medium loading rate

Abstract

Properties of unreinforced concrete and cement-based matrix are well understood. One of the issues with the cement-based matrix is its inherently brittle failure when exposed to loading. As such, steel fibers were proposed to enhance the ductility of cement-based and concrete materials. Ever since, Fiber-Reinforced Concrete (FRC) has become a commonly used building material in many construction activities such as bridges, airport pavements, shotcrete, and many others. According to previous research, the addition of steel fibers, typically from 20 to 50 kg/m3 into the conventional concrete, can significantly enhance many of the desired engineering properties of hardened concrete such as flexural strength, tensile strength, micro-cracks as well as splitting. This research presents a study aimed to numerically investigate the influence of steel fibers on the dynamic behavior of Plain Concrete (PC) exposed the tensile loading at medium strain-rate. The influence of steel fibers is investigated using different fiber volume fractions ranging from 0.0 to 4.5%. The Modified Split-Hopkinson-Bar (MSHB) apparatus is employed to investigate the dynamic tensile behavior of PC and Steel Fiber-Reinforced Concrete (SFRC). Validation of the finite element model and constitutive material behavior is carried out with the comparison of computed and measured experimental pull-back velocities of the specimen’s free end. The results showed that impact properties of steel fibers exhibit significant improvement in the toughness and the dynamic tensile strength of concrete and higher fiber volume fraction is more effective in enhancing the mechanical properties of SFRC composite.

Kinetic response of reinforced concrete slabs to high-velocity projectile impact-robust numerical and statistical driven modeling techniques

“…The LS-Dyna finite element code provides a diverse range of material formulations that can be employed to characterize the mechanical behavior of concrete and cement-based composites subjected to impact loading. Previous research has extensively examined and evaluated various material models to ascertain their effectiveness in representing concrete's response under impact conditions, as explored in (Babiker 2021;Babiker et al 2022). In light of this approach, the continuous surface cap model (*Mat 159), Schwer & Murray cap model (*Mat 145), and Karagozian & Case concrete model (*Mat 072R3) were considered as potential options.…”

Numerical Study on the Pull-out Behavior of Steel Fibers in Cement-Based Composites

“…This allows the verification of the simulated results with the experimental ones. Within previous studies, a large number of constitutive material formulations in the LS-Dyna finite element were investigated and analyzed by many researchers to their capabilities of modeling such types of bond problems (Babiker et al, 2022;Fang & Zhang, 2013).…”