Stress-strain models and numerical simulations of steel headed studs at low temperatures

Headed studs are commonly used in steel-concrete composite (SCC) structures. To promote the application of SCC structures in cold regions, this study first developed prediction equations for key indexes in temperatures ranging from 20 to-80 degrees C. Then, full-range stress-strain (sigma-epsilon) models of headed studs considering low temperatures were proposed. Validations against 56 tensile test results confirmed that the developed constitutive models accurately estimated the stress-strain behaviour of headed studs at low temperatures. Subsequently, finite element models along with the continuum damage plasticity model (CDM) and proposed sigma-epsilon models were developed for headed studs at varying temperatures. Using the test results combined with finite element analyses, the true stress-strain curve and stress-modified critical strain model were calibrated for headed studs at low temperatures. Finally, the reliability of the developed CDM and sigma-epsilon models were validated by applying them to finite element models of six pull-out and eight push-out specimens.