Efficient Prestressed Concrete-Steel Composite Girder for Medium-Span Bridges. II: Finite-Element Analysis and Experimental Investigation

In this paper, finite-element analysis (FEA) of the prestressed concrete-steel composite (PCSC) girder is performed to investigate strain and stress distributions in the girder sections and determine the influence of stud distribution on stresses in the concrete bottom flange. Approaches of FEA are discussed for the material and element models of steel, concrete, and strands, and element models of the bond between the concrete and strand and the shear studs, loading and boundary conditions, and convergence issues. A PCSC girder specimen is fabricated and instrumented in the structural laboratory to validate the proposed fabrication and design procedures. FEA and service design using the age-adjusted elasticity modulus method (AEMM) are both validated using the strain profiles at different sections and values of concrete surface strains and camber/deflection. Test results indicate that the cracking moment, ultimate moment, and ultimate shear of the PCSC girder can be well predicted using the AEMM and the AASHTO LRFD bridge design specifications.