A simple method to determine the tertiary flow in repeated load test: A step-wise method

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Conference Proceeding

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The objective of this paper is to present a new approach to determine the flow number of asphalt mixtures during dynamic creep test. A number of research studies have focused on the relationship between material properties and pavement performance. The Superpave Simple Performance Tests (SPT) is part of the efforts in past few years. One of the Superpave SPT was the repeated loading or dynamic creep test. The output of this test is the flow number, which is the initiation of tertiary flow. A common method in examining the flow number is to locate the lowest point in the strain rate versus cycle number curve. However this method may provide confusion due to the variation of the testing data. A new method was developed and evaluated in this paper. In this process, it was assumed that the strain would only increase along with time. Then the flow number at the minimum point of new strain rate versus cycle number was determined. It was found that the flow number result from this new method is more consistent and practical compared to other methods for determining the flow number. Copyright ASCE 2008.

Publication Title

Proceedings of the Symposium on Pavement Mechanics and Materials at the Inaugural International Conference of the Engineering Mechanics Institute - Pavements and Materials 2008: Modeling, Testing, and