题名: |
EVALUATION OF THE SUPERPAVE
GYRATORY COMPACTOR FOR LOW
VOLUME ROADS |
作者: |
Stephen A. Cross and Johnson Choho Lee |
关键词: |
Aggregate, Asphalt Cement, Superpave, Superpave
Gyratory Compactor |
摘要: |
There is evidence that some Kansas mixes, which have performed well in the past, will not meet the currently proposed design requirements for a Superpave level I mix. The major problem is low voids in the mineral aggregate (VMA). The major reasons for low VMA are the high amounts of natural sand currently used and the higher compactive effort required by Superpave compared to 50-blow Marshall compaction.
Cores, plant produced (field) mix, the original aggregates and asphalt cement were obtained from four low volume pavements. The cores established the in-place density of the pavements. The field mix was compacted in the Superpave Gyratory Compactor (SGC) to establish the number of gyrations required to reach the field density of the mix. The aggregates and asphalt cement were obtained and Superpave mix designs were performed. The void properties were evaluated at the original and revised gyrations. The effect of reducing the ram pressure from 600 kPa to 400 kPa was evaluated as well.
Even the revised gyrations produce samples with densities higher than both 50-blow Marshall compaction and what was found in-place. VMA was the void parameter that controlled Superpave mix designs. Converting from Marshall to Superpave mixes will require new designs. Implementing the revised ^design requirements will ease the burden of converting from Marshall to Superpave mixes.
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报告类型: |
科技报告 |