Static Behavior of Noncomposite Concrete Bridge Decks under Concentrated Loads

Tests were conducted under a concentrated monotonically increasing static wheel load on 1/6.6-scale physical models of three different types of noncomposite deck structure: (1) the entire deck supported on four steel girders; (2) an isolated deck slab region with a width equal to 1/3 of the bridge span; and (3) a 102-mm-wide transverse “beam” deck strip, both simply supported on two opposite edges on adjacent girders. Three reinforcing arrangements for the noncomposite concrete deck are studied: (1) orthotropic steel reinforcement (AASHTO); (2) isotropic steel reinforcement ( Ontario 1983); and (3) “isotropic-0.2%” minimum steel reinforcement. Flexural steel and concrete strain measurements in the “beam” deck strip models are compared with those in the models of the entire bridge deck where combined membrane compression and bending is present. Depending on the degree of the lateral and/or rotational edge restraint of the deck specimens, the ultimate load-carrying capacity of the models of the entire bridge deck ranges from five to 10 times that of the “beam” deck strips. Although some of the deck models failed primarily in flexure, all of them eventually punched through at a maximum deck deflection of less than 50% of the deck thickness.