METHODS :In this research, the aggregate slump test and angularity test were performed as fundamental laboratory tests to determine input parameters of spherical particles in DEM. The heights spreads, weights of the simple tests were measured and used to calibrate rolling and static friction coefficients of particles.
RESULTS :The DEM simulations with calibrated parameters showed good agreement with the laboratory test results for given dynamic condition.
CONCLUSIONS :It is concluded that the employed calibration method can be applicable to determine rolling friction coefficient of DEM simulation for given dynamic conditions. However, further research is necessary to connect the result to the behavior of aggregate in packing and mixing process and to refine static friction coefficient.
PURPOSES :To characterize the aging effect on asphalt binder, dynamic shear modulus mastercurve of two typical asphalt binders are developed.
METHODS :To develop dynamic shear modulus mastercurve, dynamic shear modulus at high temperature and creep stiffness at low temperature are measured by temperature sweep test and bending beam rheometer test, respectively.
RESULTS :It is observed that the aging effect on asphalt binder can be clearly observed from dynamic shear modulus mastercurve and the mastercurve can be utilized to predict behavior of asphalt binder at wide range of temperature CONCLUSIONS : It is confirmed that SBS 5% modified binder has more desirable mechanical property at low and high temperature as a pavement material comparing to PG64-22 binder and the mastercurve is an effective tool to evaluate the property of asphalt binder.
PURPOSES :Simulation of aggregate slump test using equivalent sphere particle in DEM and its validity evaluation against lab aggregate slump test
METHODS :In this research, aggregate slump tests are performed and compared with DEM simulation. To utilize spheric particles in YADE, equivalent sphere diameter concept is applied. As verification measures, the volume in slump cone filled with aggregate is used and it is compared with volume in slump cone filled with equivalent sphere particle. Slump height and diameter are also used to evaluate the suggested numerical method with equivalent concept RESULTS : Simulation test results show good agrement with lab test results in terms of loose packing volume, height and diameter of slumped particle clump.
CONCLUSIONS :It is concluded that numerical simulation using DEM is applicable to evaluate the effect of aggregate morphological property in loose packing and optimum gradation determination based on the aggregate slump test simulation result.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.