Dr. Jiong Hu
Date of this Version
Abdigaliyev, A. (2019). Evaluation Of Internally Cured Bridge Deck Concrete With Standard And Optimized Aggregate Gradation (Master's Thesis). University of Nebraska-Lincoln, Omaha, USA
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.
Advisor: Jiong Hu