| Title |
Evaluation of the Relationship between Geogrid Rib Size and Particle Size Distribution of Ballast Materials using Discrete Element Method |
| Authors |
피지현(Pi, Ji-Hyun) ; 오정호(Oh, Jeongho) |
| DOI |
https://doi.org/10.12652/Ksce.2016.36.1.0143 |
| Keywords |
지오그리드;직접 전단 실험;입도 분포도;개별 요소법 Geogrid;Direct shear test;Particle size distribution;Discrete element method |
| Abstract |
This study evaluated the shear behavior of geogrid reinforced ballast material using a large scale direct shear test and discrete element method (DEM) based on PFC 3D program. The direct shear test was conducted on ballast materials that have different particle size distributions. Whereas the test results revealed that the shear strength generally increased with the larger particle size of ballast material without geogrid reinforcement, the shear behavior of ballast material was found to change pertaining to the relationship between particle size distribution and geogrid rib size. Generally, it is deemed the effectiveness of reinforcement can be achieved when the rib size is two times greater than average particle size. A numerical analysis based on DEM was conducted to verify the test results. The geogrid modeling was successfully completed by calibration process along with sensitivity analysis to have actual tensile strength provided by manufacturer. With a given geogrid model, the parametric evaluation was further carried out to examine the interactive behavior between geogrid and ballast material. Consequently, it was found that the effectiveness zone of geogrid reinforcement generated within a specific depth. |