Rate-dependent constitutive models of S690 high-strength structural steel

Experimental and numerical investigations on seismic responses of reinforced concrete structures considering strain rate effect

Transverse impact behavior of high-strength concrete filled normal-/high-strength square steel tube columns

High-strength structural steel is the tendency in modern construction practice. In this study, quasi-static tension tests and dynamic tests for Q550 with strain rate from 0.00025 to 3831 s−1 were conducted. The results showed that Q550 is dependent on the strain rate, keeping the flow stress increased as the strain rate increases, while Q550 has lower strain-rate sensitivity of flow stress than that of normal mild steel. Based on the experimental data, a proper constant for the key parameter, C, in Johnson–Cook model (J–C) was suggested. Then, a modified J–C model based on a rate-dependent parameter $$C\left( {\dot{\varepsilon }} \right)$$ was recommended to consider the influence of strain-rate effect. New constants of D and p governing the dynamic response of steel in the Cowper–Symonds (C–S) model were also suggested. The C–S model and J–C models with suggested constants provided in the paper were proven to have acceptable prediction accuracy for the dynamic increase factor of Q550. These results may be applied to study the dynamical properties of Q550 and related structural components for future engineering applications.

Jinwei Li

Papers

Experiment research on rate-dependent constitutive model of Q420 steel