USE OF DISCRETE ELEMENT MODELING TO CAPTURE THE EFFECT OF BACKFILL PARTICLE SIZE ON THE SOIL RESTRAINTS OF BURIED PIPELINES SUBJECTED TO LATERAL GROUND MOVEMENT

Geotechnical hazards can be a major cause of damage to pipelines, particularly as a result of unacceptable strains induced in buried pipelines due to permanent ground deformations. The common design philosophy in reducing soil restraint involves taking measures to effectively isolate the pipeline from the anticipated surrounding soil movements. One of the important engineering design considerations in this regard is the selection of suitable trench backfill material(s). Full-scale model tests have revealed that, in addition to the internal friction angle, coarseness of the backfill material is also an important parameter in controlling the lateral soil restraints on the pipes due to ground movements. It can be demonstrated that discrete element approach is suitable to study the effect of particle size on lateral soil loads of buried pipelines subjected to ground movement. This paper describes the outcome from DEM numerical modeling of the response of buried pipelines subjected to lateral ground movements, with a comparison of the findings with experimental results.