Flexural strength and ductility of reinforced and partially prestressed concrete sections with corrugated steel web(s)

Abstract

Prestressed concrete bridges with corrugated steel web(s) have emerged as one of the promising bridge forms. This structural form provides excellent structural efficiency with the concrete flanges primarily taking bending and the corrugated steel webs taking shear. In the design of this type of bridges, especially those with flanges made of high-strength concrete and those with the requirement of earthquake resistance, both the flexural strength and ductility need to be carefully examined. Evaluation of these safety-related attributes requires the estimation of full-range behaviour. In this study, the full-range behaviour is evaluated by means of a nonlinear analytical method which uses the actual stress-strain curves of the materials and considers the path-dependence of materials. In view of the different behaviour of components and the large shear deformation of webs with negligible longitudinal stiffness, the assumption that plane sections remain plane may no longer be valid. The interaction between shear deformation and local bending of flanges may cause additional stress in flanges, which is considered in this study. The numerical results obtained are compared with experimental results for verification. An extensive parametric study is undertaken to clarify the effects on strength and ductility of various parameters such as the grade of concrete, the grade of non-prestressing steel, the reinforcing index, the partial prestressing ratio, and the degree of prestressing. From the numerical results, the flexural strength and ductility are investigated and some design recommendations are obtained.