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The contractor utilized the same equipment and construction process for the placement of the three different mixtures. Additionally all three of the mixtures were placed and compacted in an identical manner. Paving was accomplished by belly dumps depositing mixture in a windrow and a pick-up machine depositing the mix into the paver hopper. This is the conventional method that is typically done throughout this region. The paver was a Caterpillar model AP-1055B that used a sonic ski and slope control device to provide grade and slope control. The pick-up machine was a Barber Green BG-650.
Compaction was accomplished using two Ingersoll Rand vibratory steel drum rollers, model number DD-130HF, working in echelon as the breakdown rollers. Seven vibratory passes (a pass is defined as one trip of a roller in one direction) were needed to compact the mixture above the minimum density specification of 91 percent of maximum theoretical density. Finish rolling was provided by three passes of an Ingersoll Rand single steel wheel roller model SD-77DA. Based on nuclear gage readings, a small increase in density was provided by the finish rolling; however, the majority of the compaction effort was accomplished during breakdown rolling. No intermediate rolling was needed or provided during construction.
The roller pattern was established during the construction of a control strip. The specifications required that a control strip be placed and evaluated prior to full scale production. The evaluation of the control strip ensured that the plant was producing mixture within the tolerances of the mix design and the roller pattern used provided sufficient density. Upon completion and evaluation of the control strip, it was determined that the established roller pattern presented above would provide the necessary compactive effort. The control strip was placed and evaluated on August 21, 2007.
Bill Grants Federal Requirements Seminar 
An introductory webinar to assist local and tribal agencies with applying for transportation funding under the Bipartisan Infrastructure Law (BIL).
