Modeling of Creep Behavior of High Strength Steel H-SA700 Columns at Elevated Temperature

Abstract

Creeps is a significant component affecting steel's behavior at elevated temperatures. This paper describes an approach for using Abaqus finite element models to investigate the creep behavior of high strength steel H-SA700 with a yield strength of at least 700 MPa under high temperature conditions. The creep models developed in this research were used to characterize the creep behavior of steel column. They were based on a set of tensile tests conducted at temperatures ranging from 23 ° C to 600 ° C under constant temperature conditions. The mechanical properties of steel were adopted from the tensile test specified by JIS G 0567. The results of the tensile tests indicated that creep effects occur when the temperature of steel exceeds 400 ° C and the creep effect is regarded to be strongest at 500 ° C. Additionally, a user subroutine CREEP was designed to account for the creep effect of the high strength steel H-SA700. The factors affecting the time-dependent behavior of high strength steel, including the initial imperfection of columns, have been explored. The thermal expansion coefficients of this steel have been also identified. Taking creep behavior into account, it could be able to reasonably simulate the behavior of H-SA700 column during a fire test. Furthermore, this paper develops and explains a process for determining steel creep parameters without creep tests, which can be used to forecast the time-dependent behavior of other steel structures. on the general high temperature tensile test without doing creep test. The application of the developed method in considering thermal creep of steel at elevated temperatures conditions is further shown through the study of time dependent response of a column subjected to a fire. Finally, this paper develops and discusses the procedure for determining steel creep parameters and applying them to predict the creep behavior of other steel structures.