Experimental-Statistical Investigation of Testing Variables of a Semicircular Bending (SCB) Fracture Test Repeatability for Bituminous Mixtures
| Autor: | Yong-Rak Kim, Taesun You, Gabriel Nsengiyumva |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
Materials science
business.industry Mechanical Engineering 0211 other engineering and technologies Fracture mechanics 02 engineering and technology Repeatability Bending Asphalt concrete Cracking 020303 mechanical engineering & transports 0203 mechanical engineering Mechanics of Materials Asphalt Sample size determination 021105 building & construction Fracture (geology) General Materials Science Composite material business |
| Zdroj: | Journal of Testing and Evaluation. 45:20160103 |
| ISSN: | 0090-3973 |
| DOI: | 10.1520/jte20160103 |
| Popis: | Given the fact that fracture is a primary distress causing pavement failure, it is important to identify and characterize the fracture/cracking properties of asphalt concrete mixtures and to include them in pavement design processes. This study examined the testing variables for a reliable and practical semicircular bending (SCB) fracture test to evaluate the fracture characteristics of asphalt concrete mixtures at intermediate service temperatures. An integrated experimental-statistical approach was employed to identify testing variables by which repeatable SCB test results can be achieved. Using a typical Nebraska asphalt mixture, five critical testing variables (i.e., the number of testing specimens, specimen thickness, notch length, loading rate, and testing temperature) of the SCB test were investigated due to their significant effects on mixture fracture characteristics. Statistical analysis of test results indicated that approximately six specimens/replicates were a reasonable sample size that could properly represent asphalt concrete fracture behavior of a typical dense-graded mixture. Then, the coefficient of variation (COV) of the mixture fracture energy for six specimens was used to evaluate the effects of other remaining test variables. A range of a specimen thickness of 40 to 60 mm, a notch length from 5 to 40 mm, and a testing temperature between 15 and 40°C showed the reasonably low COV value of fracture energy at around or less than 10 %. The loading rates (0.1 to 10 mm/min.) attempted in this study did not show any significant differences in the testing repeatability. |
| Databáze: | OpenAIRE |
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