PCI eLearning Course T220: Production and Construction Details of Full-Depth Precast Concrete Deck Panels-Second-Generation, Full-Depth, Precast Concrete Deck System

Second-Generation, Full-Depth, Precast Concrete Deck System

Pdf Summary

The Nebraska Department of Roads (DOR) has developed a second-generation, full-depth, precast concrete deck system called NUDECK, which offers improved quality and reduced construction time compared to traditional cast-in-place concrete decks. The new system eliminates the variability caused by weather conditions and curing techniques, reducing the risk of shrinkage cracking. The proposed system uses longer panels to reduce the number of panels and transverse joints, and increases the spacing between shear connectors to simplify fabrication and minimize conflicts during erection. The use of covered pockets with limited penetration creates a more durable deck surface that does not require an overlay. Placing posttensioning strands over each girder line simplifies the operation of posttensioning and eliminates the need for threading strands and grouting embedded ducts. Several analytical and experimental investigations were conducted to evaluate the new system's structural performance and constructability. Testing of a complete demonstration specimen showed that the measured capacity of the proposed system exceeded the predicted capacity of a fully composite system. The Nebraska DOR is implementing the second generation of NUDECK in the construction of the Kearney East Bypass. Benefits of the new system include the ability to produce precast concrete deck panels easily with high-performance concrete, the elimination of projection of bars or inserts that require special forming, and the use of self-consolidating concrete to fill the pockets and haunch. The system is expected to be competitive with cast-in-place deck construction in terms of cost.

Keywords

NUDECK

precast concrete deck system

construction time

shrinkage cracking

longer panels

shear connectors

durable deck surface

posttensioning strands

structural performance

cost