A New Precast Concrete Deck System for Accelerated Bridge Construction

Full-depth precast concrete (PC) deck systems have several advantages over cast-in-place concrete decks in bridge construction, such as improved product quality, reduced construction labor and duration, and less dependence on weather and site conditions. This article presents he development of a new full-depth PC deck system that overcomes the drawbacks of existing systems, which include large numbers of joints and openings that need to be field cast, a requirement for tight tolerances in panel production and erection, a need for an overlay, and a complexity of post-tensioning and grouting operations. The developed deck system consists of full-depth, full-width PC deck panels that are 12 ft (3.66 m) long to minimize the number of transverse joints that need to be field cast. Panels have covered shear pockets at 4-ft (1.22 m) spacing over each girder line. These pockets are designed to minimize the number of shear connectors and deck surface penetrations to eliminate deck overlay. Deck panels are prestressed in both directions: pre-tensioned in the transverse direction and post-tensioned in the longitudinal direction using a new approach that is ductless and easy to install. These unique features are expected to enhance deck constructability, durability, and economy. The article presents the deck system design, construction sequence, and laboratory investigations conducted prior to its implementation in the construction of the Kearney East Bypass bridge in the State of Nebraska, USA.