Download or read book Forensic Investigation of AC and PCC Pavements with Extended Service Life written by Shad M. Sargand and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of this research was to identify flexible and rigid pavements in Ohio with average and above average performance, and determine the reasons for these differences in performance. The identification and implementation of factors linked to extended service life will improve performance statewide. FWD and ride quality profiles were measured to evaluate project uniformity, and material samples were obtained from a selected location on each project and tested in the laboratory to determine material properties. Volume 1 of the report includes: the project selection process, FWD and ride quality data, laboratory results of testing on base, subgrade and asphalt concrete pavement samples, and projected service lives using FWD data and the MEPDG. Volume 2 provides results of the laboratory tests and petrographic examinations of the Portland cement concrete cores. Volume 3 contains petrographic analysis of PCC pavement specimens in Cuyahoga County, Ohio containing Blast Furnace Slag Aggregate. Flexible and rigid pavements in Ohio having no structural maintenance show an average condition rating of 68 after 20 and 30 years of service, respectively. This performance, coupled with the general lack of structural distress observed on pavements selected for study indicates pavement design procedures used in Ohio are meeting expectations. Practices recommended to improve pavement performance include: 1) constructing stiffer and more uniform subgrades to provide better support and minimize localized failures, 2) reducing amounts of Portland cement and using larger aggregate in 451 and 452 concrete, while continuing to screen aggregate for D-cracking susceptibility, 3) increasing emphasis on ensuring that dowel bars maintain proper alignment during PC concrete placement, and 4) continuing the use of performance grading, smaller aggregate and polymers in AC mixes on heavily traveled pavements. Other observations regarding data used to reach these conclusions include: keeping the PMIS database current, retaining construction records for at least the design life of the pavements, being aware that the effect of surface cracks on flexible pavement performance depends upon whether the cracks are top-down or bottom-up, and keeping the PMIS and straight-line diagrams consistent in identifying project limits, project numbers and paving materials.