Internal Curing of Concrete Bridge Decks in Utah
Internal Curing of Concrete Bridge Decks in Utah

Author: Joseph Michael Yaede

Publisher:

Published: 2013

Total Pages: 97

ISBN-13:

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In the field, Schmidt rebound hammer testing showed that the internally cured concrete was neither consistently stronger nor weaker than the conventional concrete. On average, the internally cured concrete exhibited higher chloride concentrations than the conventional concrete. On average, the conventional concrete bridge decks had 4.6, 21.5, and 2.8 times more cracking than the internally cured concrete decks at 5 months, 8 months, and 1 year, respectively. At 1 year, very distinctive reflection cracks from the joints between the underlying pre-cast half-deck panels were observed on all of the decks.

Evaluation of Internally Cured Bridge Deck Concrete with Standard and Optimized Aggregate Gradation
Evaluation of Internally Cured Bridge Deck Concrete with Standard and Optimized Aggregate Gradation

Author: Arman Abdigaliyev

Publisher:

Published: 2019

Total Pages: 117

ISBN-13:

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Due to the relatively high cement content and low water-to-cement ratio (w/c) used, bridge deck concrete is prone to premature cracking. Internal curing has been found to greatly reduce the chance of premature cracking as well as concrete deterioration. This research developed internally cured bridge deck concrete based on a local mix design in Nebraska. Four different lightweight fine aggregate (LWFA) as internal curing agents were evaluated and their effects on fresh, mechanical, durability, and shrinkage properties of concrete were studied. The study focused on resolving two issues associated with fine aggregate replacement based on Bentz equation. To identify the most effective LWFA dosage for shrinkage reduction, different replacement rates of fine aggregates (50%, 100%, 125%, 150% and 175%) were adopted to account for the moisture loss during construction and drying period. Aggregate blends of internally cured mixes were also optimized to account for the disturbed aggregate gradations due to the introduced LWFA. Overall performance of internally cured concrete mixes with both non-optimized and optimized gradations were evaluated. The research demonstrated that effective internal curing concrete can be achieved with the optimized aggregate gradation.

Curing Practices to Reduce Plastic Shrinkage in Concrete Bridge Decks
Curing Practices to Reduce Plastic Shrinkage in Concrete Bridge Decks

Author: Steven W. Peyton

Publisher:

Published: 2011

Total Pages:

ISBN-13:

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"The large, exposed area of concrete bridge decks makes proper curing critical and difficult. Plastic shrinkage cracks are common in improperly cured bridge decks. The objective of this research was to identify curing regimens that successfully reduce plastic shrinkage cracking. This was accomplished by surveying Arkansas Highway and Transportation Department engineers to determine the current construction practices on Arkansas bridge decks, documenting the curing of five bridge decks under construction, and studying the effectiveness of curing regimens in the laboratory. The survey responses show inconsistencies in the interpretations of the construction specifications that were also evident in the field study. Delayed curing, high evaporation rate, and increased girder deflection increased the likelihood of cracking in the decks. Inconsistent application of curing materials caused increased cracking in the laboratory study. Removing impediments, such as tined finishes, to timely curing and clarifying curing specifications would reduce cracking in bridge decks."--Project summary.