Strength of shear connection in composite bridges with precast decks using high performance concrete and shear-keys

In this paper, a connection between precast beam and precast slab to be used in decks of precast composite bridges is studied. The difference between this connection and the common connection used in bridge construction is that in this paper the steel connector is associated with a shear-key, which is formed on the top face of the precast beam, and a high performance concrete is used to fill out the shear pockets. The connector is formed by steel bars bent in a hoop form, which are inserted in pockets of the precast slab. The connection is made filling out the shear pockets with steel fiber reinforced concrete. Push-out tests were carried Out to evaluate the strength of the shear connection. From these tests expressions based on a shearfriction model are proposed to evaluate the strength of the shear connection taking into account the compressive strength of the concrete cast in the pocket, the diameter of the connector and the addition of steel fibers to cast-in-place concrete. These expressions were shown to be appropriate to evaluate the strength of a shear connection, since the failure of precast concrete is avoided near the connection, 1359-5997 (c) 2004 RILEM. All rights reserved.