Interface horizontal shear strength in composite decks with precast concrete panels

Six stay-in-place precast, prestressed deck panels were tested to evaluate the horizontal shear strength between the precast panel and the cast-in-place portion of the bridge deck. Presently, the Indiana Department of Transportation requires a minimum of 20 shear connectors regardless of panel dimensions. The shear connectors are placed across a broom finished deck panel surface. Broom finish with approximately 0.05 to 0.075 in. (1.27 to 1.91 mm) total amplitude deformations is specified instead of a raked finish with 0,25 in. (6.35 mm) total amplitude because of the reduced 2.5 in. (63.5 mm) thickness of the panels used in Indiana. In this study, composite behavior at ultimate, including horizontal shear and interface slip characteristics, was evaluated. It is concluded that stay-in-place precast, prestressed deck panels with a broom finished surface do not require horizontal shear connectors if the nominal average horizontal shear stress at the interface is less than 116 psi (0.8 MPa).