Preliminary Laboratory Evaluation of Fiber Reinforced Asphalt Concrete

The South Dakota Department of Transportation (SDDOT) has been invited to participate in research on the use of fiber-reinforced asphalt concrete by the Civil Engineering Department at the South Dakota School of Mines & Technology (SDSM&T). Dr. Lance Roberts at SDSM&T will be conducting a preliminary laboratory experimental program to assess the applicability of this new technology within South Dakota's climatic and environmental conditions, and using typical South Dakota aggregate sources and asphalt binder materials as well. Forta Corporation, manufacturer of the synthetic fiber material, has agreed to pay for the fiber, as well as the evaluation to be performed by Dr. Roberts. Also, the Cities of Rapid City and Sioux Falls have agreed to construct test sections on respective street projects during the current construction season. The SDDOT Research Review Board has authorized SDDOT's Office of Research to monitor the work, comprising construction documentation and laboratory testing of the material, using its normal technical panel process. The laboratory experimental program defined for SDSM&T will utilize advanced material characterization tests to evaluate the mechanical properties of fiber reinforced hot mix asphalt (HMA). Additionally, the pavement construction project in Rapid City will be observed and documented to substantiate field conditions and placement. The research effort will ultimately be aimed at determining whether subsequent detailed analysis of fiber reinforcement in typical asphalt mixes in South Dakota would be warranted, and also to characterize these mixes with respect to the Mechanistic-Empirical Pavement Design Guide (M-EPDG) principles that are currently under systematic implementation at the SDDOT. The objectives of this project are to: (1) observe and document the field placement of forty (40) tons of fiber reinforced HMA material on a pavement project coordinated with the City of Rapid City. During the time of construction, samples of the fiber reinforced HMA, along with samples of a conventional (control) HMA mix, will be collected for laboratory testing; (2)conduct preliminary laboratory experimental testing of the fiber reinforced HMA mix, along with the conventional (control) HMA mix, obtained from the Rapid City pavement project, along with a fiber reinforced and a conventional (control) HMA mix from a recently completed Sioux Falls pavement project, in order to characterize mechanical and performance properties of each mix; (3)determine if further investigation of fiber reinforced HMA is warranted based on the results of the preliminary laboratory experimental program. The preliminary laboratory experimental program will assess the feasibility, economic benefit, and improvement in pavement performance with using fiber reinforced HMA, which may lead to the need for further analysis of the technology within South Dakota; and (4) collect basic field data at the Rapid City pavement project, which would support further investigation of fiber reinforced HMA, if warranted. Research tasks of the project are as follows. (1) Observe and document the construction of a fiber reinforced HMA pavement section and a conventional (control) HMA pavement section coordinated with the City of Rapid City. (2) Perform laboratory testing of a fiber reinforced HMA mix and a control HMA mix from a pavement project site in Rapid City and in Sioux Falls. (3) Collect and summarize the basic field data for incorporation into the final report. (4) Prepare a final report and executive summary of project findings. (5) Make an executive presentation to the SDDOT Research Review Board at the conclusion of the project and after acceptance of the final report.