Nonlinear finite element modeling of dynamic localizations in high strength steel columns under impact

This paper presents a consistent methodology for the assessment of nonlinear behavior of structural steel column under severe loading conditions. Nonlinear finite element analysis is conducted to study localization failure in axially pre-loaded columns made of high strength steel HY-100 and subjected to transverse impact. The thermo-viscoplastic response of high strength steel at low and high strain rates and temperatures is also investigated using a physically based constitutive model. The constitutive model which exhibits dominant performance in describing the thermo-mechanical behavior of metals is then implemented into the commercial finite element code ABAQUS/Explicit via user material subroutine coded as VUMAT. The effect of impact velocity, impactor mass, impact location and pre-loading condition on the localization behavior of the steel columns is also investigated. The outcomes of this study could be utilized to provide some guidelines to design codes to come up with simplified method of analysis for steel structures subjected to impact loading.