Field Investigation of In-service Performance of Concrete Bridge Decks in Pennsylvania

The results of an expert survey and field investigation of early-age bridge deck cracking in the Commonwealth of Pennsylvania is summarized in this paper. The goal was to use field data to identify factors that contribute to, or reduce, early-age cracking in concrete bridge decks and to assess the effect of cracks on long-term durability performance of bridge decks. First, a survey of 71 PennDOT personnel was conducted to collect and document their experience with early-age cracking and its relation to longterm deck performance. Next, inspection data from 203 bridge decks were collected and analyzed to evaluate the effect of concrete mixture proportions and properties, construction methods, and rebar type on the propensity to experience early-age deck cracking. The inspections included 40 older bridge decks plus initial (post construction) inspection data for 163 new bridge decks that was received from PennDOT. The results suggest that limiting the total cementitious materials content (e.g., to 620 pcy) and the maximum compressive strength (e.g., to 5000 psi at 28 days) is advisable to reduce deck cracking. In addition, epoxy-coated rebar showed good corrosion resistance even in cracked concrete.