This guide provides bridge related definitions and corresponding commentaries, as well as the framework for a systematic approach to a preventive maintenance program. The goal is to provide guidance on bridge preservation. This guide is intended for Federal, State, and local bridge engineers, area engineers, bridge owners, and bridge preservation practitioners.

Transverse cracking of concrete bridge decks is problematic in numerous states. Cracking has been identified in the negative and positive moment regions of bridges and can appear shortly after opening the structure to live loads. To improve the service life of the bridge deck as well as decrease maintenance costs, changes to current construction practices in Indiana are being considered. A typical bridge deck was instrumented which incorporated the following: increased reinforcement amounts, decreasing reinforcement spacing, and high-performance, low-shrinkage concrete. The low shrinkage concrete was achieved using a ternary concrete mix. The objective of this research was to determine the performance, particularly in terms of transverse cracking and shrinkage, of a bridge incorporating design details meant to reduce cracking. Based on measurements from the bridge, it was determined that maximum tensile strains experienced in the concrete were not sufficient to initiate cracking. An on-site inspection was performed to confirm that cracking had not initiated. The data was analyzed and compared with the behavior of a similarly constructed bridge built with nearly identical reinforcing details, but with a more conventional concrete to evaluate the effect of the HPC. Based on this study, it was observed that full-depth transverse cracks did not occur in the structure and that the use of HPC lowered the magnitude of restrained shrinkage strains and resulting tensile stresses.

The objective of this research program was to examine the efficacy of using alternative materials in a bridge deck from both technical and economic perspectives. For the technical evaluation (Volume 1), a three phase experimental investigation was conducted considering a wide range of corrosion-resistant reinforcing materials. These materials included stainless steels, microcomposite steel, and coated steels considering a variety of metallic and nonmetallic coatings. The first phase evaluated the bond between corrosion-resistant reinforcement and concrete using lap splice tests. The second phase evaluated the cracking behavior of slabs reinforced with corrosion-resistant reinforcement. Finally, the third phase evaluated corrosion resistance under uncracked and cracked conditions using macrocell test specimens. Transverse steel was also tied to the longitudinal steel to simulate actual bridge deck conditions. Recommendations are provided on development and splice lengths for both conventional black and corrosion-resistant reinforcing steel, control of cracks widths, as well as the selection, design, and construction of corrosion-resistant reinforcement. For the economic evaluation (Volume 2), a decision support methodology and associated spreadsheet tool for robust analysis of the cost-effectiveness of alternative material types for bridge deck reinforcement was developed. The two evaluation criteria are agency and user costs, and the input data that influence this criteria include the deck service life, material process, discount rate, detour length, and bridge size. The methodology incorporates analytical techniques that include life cycle analyses to evaluate the long-term cost and benefits of each material over the bridge life; Monte Carlo simulation to account for the probabilistic nature of the input variables; stochastic dominance to ascertain the probability distribution of the outcome that a specific reinforcement material is superior to others; and analytical hierarchical process to establish appropriate weights for the agency and user costs. Methodology is demonstrated using a case study involving three reinforcement material alternatives: traditional (epoxy-coated) steel, zinc-clad steel, and stainless steel. Through this study, it is demonstrated that the use of corrosion-resistant reinforcing materials can significantly increase bridge deck life, reduce agency and user costs associated with bridge deck rehabilitation and maintenance, and thus lower the financial needs for long-term preservation of bridges.

With the ongoing concern about premature cracking of concrete bridge decks that reduces the service life of bridges and results in increased maintenance and replacement costs, this work aimed at assessing the benefits of using lightweight fine aggregate (LWFA) in concrete mixtures to assist the Ohio Department of Transportation (ODOT) in preparing a specification to increase the probability of achieving crack-free, long-lasting bridge decks. A laboratory testing program led to a recommended mix design for implementation on a bridge construction project in Ohio. The design included the use of 50% slag cement and LWFA for internal curing. Construction of two bridge decks involved a control using a conventional mix design and the other containing the recommended mixture. The decks were instrumented and load tested shortly after construction and inspected one year after placement. No differences in structural performance were noted, but there were far fewer cracks in the test deck compared to the control. A life-cycle cost analysis was also conducted and shown that the premium for the recommended mixture would be recovered in reduced maintenance over the life of the bridge.