AUTHORS: Bao Thach Nguyen, Abbas Mohajerani

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ABSTRACT: Over the last decade, the rapid development of the computational technology has made a significant impact on the other field of engineering; especially on the method of data analysis. Computational approach has been applied widely to investigate the engineering problem. In the current study, the application of discrete element method (DEM) is examined in simulation of the repeated load triaxial test in pavement engineering. Flexible pavement is complex structure. Under the dynamic traffic loading, the behaviour of pavement can be predicted by using the repeated load triaxial test equipment in the laboratory. However, the nature of the repeated load triaxial testing procedure is considered time-consuming, complicated and expensive, and it is a challenge to carry out as a routine test in the laboratory. Therefore, the current paper proposes a numerical approach to simulate the repeated load triaxial test by employing the discrete element method. A sample with particle size ranging from 2.36 mm to 19.0 mm was constructed. Material properties, which included normal stiffness, shear stiffness, coefficient of friction, maximum dry density and particle density, were used as the input for the simulation. The sample was then subjected to a combination of deviator and confining stress and it was found that the discrete element method is able to simulate the repeated load triaxial test in the laboratory.

KEYWORDS: Resilient behaviour, discrete element method, numerical method, dynamic load, pavement, unbound granular.

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