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AMERICAN ENGINEERING TESTING, INC. AET Project No. 22-00012 <br /> The heavy-duty pavement section can be constructed without the bituminous and used as a <br /> construction haul road. However, if the heavy-duty pavement areas are used as haul roads <br /> during construction, additional aggregate base course should be placed (over the thickness <br /> recommended above) because some of the near-surface aggregate material will become fouled <br /> by construction traffic. This fouled base course should be stripped off prior to placing the <br /> bituminous. <br /> The aggregate base course should be compacted to at least 100% of the maximum Standard <br /> Proctor dry density or to meet the penetration index criteria for Mn/DOT dynamic cone <br /> penetrometer(DCP) tests. After the base course has been placed, compacted and tested, it is the <br /> contractor's responsibility to maintain the base in a suitable condition for paving. If the subgrade <br /> becomes saturated after testing, it may be rendered unsuitable for paving due to softness and <br /> pumping. This would require remedial action before the pavement can be placed. <br /> Please note that we have specified gradation No. 3 in the wear course bituminous mix. This <br /> gradation will provide more stability and resist static loads and scuffing better than a gradation <br /> No. 4. However, please note that the gradation No. 3 mix is more "coarse" looking than a <br /> gradation No. 4, and is sometimes considered less aesthetically pleasing. For the Mn/DOT 2360 <br /> bituminous mix, the compaction should be at least 91.0% of the maximum theoretical density <br /> (G.) for placement over aggregate base course, and 92.0% for placement over a bituminous <br /> layer. We recommend using Type E oil (PG 64-28) for the wear and non-wear course for both <br /> light-duty and heavy-duty bituminous mixes. As an alternative, Type B oil (PG 58-28) could be <br /> used for the non-wear course. <br /> The bituminous pavement section given above would have an estimated life of 20 years. <br /> However, the Owner should not expect that the pavements would last 20 years without <br /> maintenance. Within one to three years after construction, cracks will appear in the bituminous <br /> mat due to thermal expansion and contraction, and due to the loss of volatiles from the <br /> bituminous cement. These cracks cannot be avoided; they should be cleaned annually and filled <br /> Page 25 of 28 <br />