Plant and Laboratory Scale Studies of High Performance Concrete for Bridge Decks in West Virginia

Full-depth precast bridge decks are widely used to expedite bridge construction and enhance durability. These deck systems face the challenge that their durability and performance are usually dictated by the effectiveness of their field joints and closure joint materials. Hence, commercial ultra-high performance concrete (UHPC) products have gained popularity for use in such joints because of their superior mechanical properties. However, the proprietary and relatively expensive nature of the robust UHPC mixes may pose some limitations on their future implementation. For these reasons, many research agencies along with state departments of transportation sought their way to develop cheaper non-proprietary UHPC (NP-UHPC) mixes using locally supplied materials. The objective of this study is to demonstrate the full-scale application of the recently developed NP-UHPC mixes at the ABC-UTC (accelerated bridge construction university transportation center) in transverse field joints of precast bridge decks. This study included experimental testing of three full-scale precast bridge deck subassemblies with transverse NP-UHPC field joints under static vertical loading. The test parameters included NP-UHPC mixes with different steel fibers amount, different joint splice details, and joint widths. The results of this study were compared with the results of a similar proprietary UHPC reference specimen. The structural behavior of the test specimens was evaluated in terms of the load versus deflection, reinforcement and concrete strains, and full assessment of the field joint performance. The study showed that the proposed NP-UHPC mixes and field joint details can be efficiently used in the transverse deck field joints with comparable behavior to the proprietary UHPC joints. The study concluded that the proposed systems remained elastic under the target design service and ultimate loads. In addition, the study showed that the use of reinforcement loop splices enhanced the load distribution across the specimen’s cross-section.

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Shrinkage in Ultra-High Performance Concrete Overlays on Concrete Bridge Decks

MATEC Web of Conferences ◽

10.1051/matecconf/201927107008 ◽

2019 ◽

Vol 271 ◽

pp. 07008

Author(s):

William Toledo ◽

Leticia Davila ◽

Ahmed Al-Basha ◽

Craig Newtson ◽

Brad Weldon

Keyword(s):

High Performance ◽

High Performance Concrete ◽

Bridge Decks ◽

Plastic State ◽

Early Age ◽

Concrete Bridge ◽

Ultra High Performance Concrete ◽

Concrete Overlays ◽

Concrete Bridge Decks ◽

Normal Strength

This paper investigates the shrinkage and thermal effects of an ultra-high performance concrete (UHPC) mixture proposed for use as an overlay material for concrete bridge decks. In this study, early-age and longer-term shrinkage tests were performed on the locally produced UHPC. Thermal and shrinkage effects in normal strength concrete slabs overlaid with UHPC were also observed. Early-age shrinkage testing showed that approximately 55% of the strain occurred in the plastic state and may not contribute to bond stresses since the elastic modulus of the UHPC should be small at such early ages. Thickness of the substrate and amount of reinforcing steel were important factors for shrinkage in the slabs. The thickest slab experienced greater shrinkage than thinner slabs. Comparing this slab to a thinner slab with the same reinforcement indicated that reinforcement ratio is more important than the area of steel.

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In-Service Performance of High-Performance Concrete Bridge Decks

Transportation Research Record Journal of the Transportation Research Board ◽

10.3141/1696-62 ◽

2000 ◽

Vol 1696 (1) ◽

pp. 193-196 ◽

Cited By ~ 2

Author(s):

Sreenivas Alampalli ◽

Frank Owens

Keyword(s):

New York ◽

High Performance ◽

Recent Literature ◽

High Performance Concrete ◽

Bridge Decks ◽

New York State ◽

Crack Density ◽

Transverse Cracking ◽

Concrete Bridge Decks ◽

Better Than

The current statewide standard for New York State bridge decks is Class HP (high-performance) concrete. This mix was introduced in April 1996 to increase deck durability by reducing cracking and permeability. Since its introduction, more than 80 bridge decks have been built with Class HP concrete. To compare the performance of Class HP concrete with that of previously specified concrete, the decks were visually inspected. Results indicated that Class HP decks performed better than previously specified concrete in resisting both longitudinal and transverse cracking. Furthermore, of the 84 decks inspected, 49 percent exhibited no cracking at all, but of those that had cracked, 88 percent exhibited equal or less longitudinal cracking and 80 percent exhibited equal or less transverse cracking than previously specified concrete. A final result showed that average transverse crack density on Class HP decks, excluding uncracked decks, was 6.9 cm/m2. This value is comparable with crack densities for other decks (not using HP mix) that were reported in recent literature.

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