Micro-Analysis Ballast-Geogrid Pull out Tests Interaction

The discrete element method was used to simulate geogrid-reinforced ballast by pull out tests. Ballast particle was made of irregular clumps where its size and shape were considered by bonded spheres. The response of the ballast reinforced with geogrid under loading agrees with pull out experimental results. The micro-interaction between ballast particle and geogrid analyzed by microscopic parameters, contact force chain, force-displacement of the pull out tests was presented. It was also proved that the shape of granular particles, geogrid size and friction played an important role in ballast-geogrid system.