Comparison of Concrete Strength Development Between Bridge Deck Cores and Concrete Test Cylinders Under Varying Curing Durations (05-1927)**
Hector Garcia, Texas Tech University
Randal Scott Phelan, Buckland & Taylor
Sanjaya P. Senadheera, Texas Tech University
Kevin Pruski, Texas Department of Transportation

With ever increasing traffic flow in urban areas, lane, road, and/or bridge closures have become an inconvenience to road users. As a result, there continues to be pressure to open concrete pavements and bridge decks to full traffic loads earlier. However, the built structure must also remain functional (i.e. durable). Durability of concrete bridge decks has long been associated with good concrete mix designs and adequate curing durations. To better assess the potential of reduced required curing times for bridge decks, the Texas Department of Transportation (TxDOT) has collaborated with Texas Tech University in a research project entitled: “Effects of Wet Mat Curing and Earlier Loading on Long-Term Durability of Bridge Decks.” In addition to required curing times, many bridge decks and concrete pavements across the country are opened to traffic once a desired compressive strength is achieved from a representative field-cast 6-inch diameter test cylinder (1). Thus, concrete strength gain and required curing duration are major factors in determining the minimal amount of time before a concrete deck or pavement can be put into use. The emphasis of this paper is to present a comparison on the effects that different wet mat curing durations have on concrete strength development – both on actual 4-inch diameter bridge deck cores and on 6-inch diameter test cylinders. This comparison is considered a first step in determining the minimum required curing duration for a bridge deck. Additional durability tests are required before allowance to earlier bridge deck loads will be granted.