Date of Graduation
Bachelor of Science in Civil Engineering
Since 1997 Arkansas asphalt mixtures have been designed using a procedure commonly known as ‘Superpave’. In a traditional Superpave mix design, the design considers only traditional volumetric parameters; however, recent advances in mix design technology emphasize mixture’s ability to perform in its environment. There are numerous factors which affect the performance characteristics of an asphalt mix. Certainly, the asphalt binder’s performance is a critical variable in this system. Asphalt binders are sensitive to temperature, so much so that their primary parameter on which they are recommended is a function of both temperature and the geographic latitude in which the pavement will ultimately reside. Additionally, binder becomes more brittle as it ages, which can be exacerbated if residing in an environment outside of the binder’s recommended temperature range. Performance-related tests are included in the binder grading specification to account for this behavior.
Recent evolution of Superpave mix designs marry these concepts by recommending various types of physical (performance-related) testing in conjunction with the volumetric mix design. In order for a mix to be judged to be acceptable, it must pass these tests. The testing recommended in this system is related to the pavement’s cracking and rutting potential.
Currently, the Arkansas Superpave system includes only a performance-related test for rutting; it does not have a defined procedure to judge cracking performance. TRC 1802 sets out to solve this problem by identifying tests in conjunction with volumetric mix designs that accurately identify early-age cracking susceptibility by recreating mix designs currently in the field. By applying cracking testing in these recreated mixes, the results can be compared to the recorded field survey data to determine how correct these early-age cracking tests are to mixes known to be or not to be cracked. These mixes in the field act as case studies and are representatives of many of the types of mixes all over the state. However, many mixes exist in the state and not all can be tested. Therefore, of the subset of mixes as provided by ARDOT, a handful must be chosen to be representative of pavements in various states of distress and these few will be fully tested. The site selection procedure outlined in this text will identify mixes to encapsulate the performance piece, bringing Arkansas into the modern era of asphalt mixture design. The site selection procedure developed in this project can serve as a template for future studies which propose to use field performance data to identify candidate materials/mixtures for additional study.
Asphalt, Site, Selection, Pavement, Materials
Richey, Allyson, "Using Historic Pavement Performance Data to Identify and Select Sites for Asphalt Mixture Design Studies" (2017). Civil Engineering Undergraduate Honors Theses. 42.