Mason Archival Repository Service

Effects of Particle Shape on Performance and Durability of Aggregates Used in Road Construction

Show simple item record

dc.contributor.advisor Tanyu, Burak Cook, Clayton
dc.creator Cook, Clayton 2015-07-08 2015-10-12T15:27:07Z 2015-10-12T15:27:07Z 2015-10-12
dc.description.abstract Based on a comprehensive review of current United States transportation agency specifications, it was found that there is a large variation in current limits set on the shape of aggregate particles that are considered as suitable to be used in an unbound base layer. Previous studies found in the literature indicated that the shape of the aggregate may affect the overall performance of the base course, but the extent of that effect has not been quantitatively documented. Therefore, a well-defined limit on particle shape for unbound aggregate base does not exist. This research is providing a detailed quantitative comparison of the effect of aggregate shape on unbound aggregate base as it relates to performance within an unbound base layer. The experimental program for this study included particle shape analyses, compaction, matrix interlocking characterization (Bailey method), resilient modulus, and permanent deformation testing. Four different types of aggregates including diabase, hornfels, dolostone, and slate were included in the study and aggregates from each rock type were separated and sieved to create varying particle shapes within the same mineralogy and open- and dense-graded aggregate gradations used in road construction. Samples with consistent mineralogy were compared with each other to understand the effect of particle shape of aggregates with a specific mineralogy and samples with different mineralogy (but with same gradation) were compared with each other to understand the variation of the findings with differences in mineralogy. The findings of the study showed that the durability of the aggregate was dominated by the mineralogy, but marked variations in durability were observed because of particle shape. Additionally, matrix interlocking characterization by the Bailey method showed that the effect of particle shape was more pronounced in the open-graded materials since the coarse particle made up the load carrying skeleton of the structure. The overall effect of particle shape on the performance, as it was defined in this study, of typically designed flexible pavement structures appear to be minor. However, particle shape was noted to significantly affect non-typical flexible pavement structures, specifically an open-graded base layer supporting a thin asphalt surface.
dc.language.iso en en_US
dc.subject particle shape en_US
dc.subject resilient modulus en_US
dc.subject micro deval en_US
dc.subject unbound aggregate base en_US
dc.subject permanent deformation en_US
dc.subject flexible pavement en_US
dc.title Effects of Particle Shape on Performance and Durability of Aggregates Used in Road Construction en_US
dc.type Thesis en Master of Science in Civil and Infrastructure Engineering en_US Master's en Civil and Infrastructure Engineering en George Mason University en

Files in this item

This item appears in the following Collection(s)

Show simple item record

Search MARS


My Account