Thermally Induced Behavior of Paired Internally Cured Concrete and Conventional Concrete Decks in Composite Bridges

Many states have problems with transverse cracking of the concrete bridge decks. These cracks occur in negative and positive moment regions and can affect the serviceability of the decks. To improve the deck durability, internally cured concrete (ICC) has been recommended. However, limited research has been conducted to evaluate the field performance of ICC bridge decks. This paper evaluates the field behavior of an ICC deck in comparison with an adjacent conventional concrete (CC) deck exposed to thermal variations. Each deck was instrumented to monitor its behavior under environmental conditions and then compared with its performance under live loading. The results indicated that temperature fluctuations had a significant influence on the potential for deck cracking. It was observed that the ICC deck had a significantly lower cracking potential when compared with the CC deck after four months of construction. In addition, the results showed that the tensile stresses in the reinforcement of the ICC deck due to thermal variation was only 5% of the maximum allowable stresses, whereas it was only 70% of the maximum allowable stresses for the CC deck. Moreover, it was observed that both decks exhibited similar performance under the live load testing.