BACKGROUND: Self-consolidating concrete (SCC) is a specially proportioned hydraulic cement concrete that enables the fresh concrete to flow easily into the forms and around the reinforcement and prestressing steel without segregation. Use of this type of concrete for the manufacture of precast, prestressed bridge elements provides the benefits of increased rate of production and safety, reduced labor needs, and lower noise levels at manufacturing plants.
In spite of its benefits and widespread use in Japan and Europe, the use of SCC in the United States has been limited because of concerns about certain design and construction issues that are perceived to influence the structural integrity of the bridge system. These issues include workability, strength development, creep and shrinkage properties, durability, and other factors that influence constuctibility and performance.
Research is needed to address the factors that significantly influence the design, constructibility, and performance of precast, prestressed bridge elements manufactured with SCC and to develop guidelines for the use of SCC in these applications including recommended changes to AASHTO LRFD bridge specifications. These guidelines will provide highway agencies with the information necessary for considering concrete mixtures that are expected to expedite construction and yield economic and other benefits.
OBJECTIVES: The objectives of this research were (1) to develop guidelines for the use of self-consolidating concrete in precast, prestressed concrete bridge elements and (2) to recommend relevant changes to AASHTO LRFD bridge design and construction specifications.
Status: The project is complete; the final report, NCHRP Report 628: Self-Consolidating Concrete for Precast, Prestressed Concrete Bridge Elements is available for purchase and/or download.