Comparison Of Conventional And Internally Cured Concrete Bridge Decks In Utah Mountain View Corridor Project PDF Download

The long-term performance of a bridge deck depends on its resistance to bridge cracking. Most of these cracks are initiated at the early age. Early age cracking of bridge decks is a typical issue in the U.S. that reduces bridge service life. Therefore, internally cured concrete (ICC) has been used in some states to reduce or eliminate the development of cracks in reinforced concrete decks. In this study, the early age behavior of ICC deck and the effect of the internal curing on the long-term behavior of the bridge was measured and evaluated in the laboratory and field for newly adjacent constructed bridge, which were located on Route 271 in Mayfield, Ohio. Two different types of concrete mixtures were utilized for the decks: conventional concrete (CC) and internally cured concrete (ICC). Firstly, the ICC and CC mixtures were examined in the laboratory in terms of a mechanical properties test, a plastic shrinkage test, a free shrinkage test, and a restrained shrinkage test. Second, the field behavior of an ICC deck and an adjacent CC deck during their early age and long-term performance were evaluated. Also, the shrinkage development for both decks was examined during the very early age. Instrumentation was used to measure the concrete and reinforcement strains and the temperature in both bridges. The instrumentation and results for both bridges are discussed. Laboratory results indicated that using pre-wetted lightweight concrete in the concrete mixture led to decreased density, coefficient of thermal expansion, and free shrinkage strain, and increased tensile strength and cracking time of concrete compared to conventional concrete. In the field, from the early age test, it was observed that the time to develop concrete shrinkage was approximately 5-6 hours after casting the deck of the ICC and the CC.