Innovative Bridge Research and Construction

The South Dakota Department of Transportation (SDDOT) submitted an successful application for $330,000 in funding as part of the TEA-21 Innovative Bridge Construction Program. This research is designed to meet the evaluation requirements of this experimental bridge construction. Four new bridges have been selected for inclusion in the research-50-177-199, 50-178-199; 50-175-207, 50-176-207- as part of IM29-3(38)79 PCEMS A443 in Minnehaha County. The bridges include 1) Madison Street over I-29 and 2) I-29 over a railroad and have the following design details: 1) Two 3-span steel girder bridges, each 374' x 56' roadway; and 2) Two single-span steel girder brides, one 94' x 93.5' roadway and another 94' x 83.5' roadway. The intent is to use corrosion resistant 316L clad reinforcing steel bar in one set of bridges and corrosion resistant 2205 duplex stainless steel reinforcement in the other set. This will be in conjunction with low permeability, optimized gradation concrete for the decks. This combination of materials will combine application of three recent SDDOT research efforts to: optimize fly ash content for low permeability (SD 2000-06); optimize aggregate gradation to provide strength while minimizing shrinkage cracking SD 2002-02); and use non-corrosive, stainless steel clad reinforcing steel (SD 2002-16). The goal of this combination is a design for new bridge decks that can reliably achieve a 75-year life with minimal deck maintenance. This research addresses the evaluation of the innovative construction materials used and the initial performance of the structures. The objectives of this research project are toves: (1) determine the constructability of the bridge decks with the optimized concrete mixture and corrosion-resistant reinforcement; (2) evaluate the performance of the bridge decks especially with respect to cracking frequency; and (3) assess the overall benefits of the optimized bridge decks with respect to achieving a 75-year life. Research tasks for this project are as follows: (1) Develop a workplan incorporating previous SDDOT and other research results for monitoring construction and evaluating performance of the experimental bridges. (2) Verify duplex and stainless clad reinforcement physical properties through appropriate routine testing. (3) Document the concrete mixture design and physical properties for the proposed optimized mixture. (4) Monitor construction of the four bridge decks, determine as-delivered reinforcement properties (dimension, cladding thickness, physical tests) and record all concrete mixture test results. (5) Conduct an extensive cracking and condition survey on each bridge prior to its being opened to traffic. (6) Submit an interim construction and initial evaluation report on the four bridges. (7) Conduct permeability and other appropriate testing on each bridge at 28 days, 1 year and 2 years after construction. (8) Perform and report on interim evaluations at 6 months, 1 year and two years after construction is complete. (9) Prepare a final report and executive summary of the prior research, research methodology, findings, conclusions and recommendations. (10) Make an executive presentation to the SDDOT Research Review Board at the conclusion of the project.