Nominal flexural resistances in positive bending for composite I-girder sections using high strength steel with strain hardening

Abstract

This study presents a new nominal flexural resistance of composite I-girder sections using high strength steel, HSB460, with strain-hardening in the positive bending region. An extensive parametric study using the strain compatibility method was conducted on a wide range of composite girder sections for calculating flexural strengths. On the basis of the results of the parametric study, a factor that accounts for the effect of strain hardening of HSB460 steel on the flexural strength of composite I-girder sections is suggested as a function of the ductility ratio. A new nominal flexural resistance for the composite HSB460 girder sections is then proposed as the product of the nominal flexural resistance in the AASHTO LRFD bridge design specifications and the strain-hardening factor