A major issue in the enduring performance of embankments subjected torepeated loading is its progressive deformation and loss of strength over time. Inparticular, railroad ballast embankments are prone to a rapid loss of geometry underloading by heavy freight trains. This deterioration manifests itself with high rate oftrack geometry loss, costing many millions of dollars each year by requiring frequentmaintenance that can disrupt train schedule. The objective of this work was tosimulate repeated loading on a ballast embankment, exploring a promisingmethodology to slow the deterioration process. A series of 6 loading tests onidealized representations of railroad ballast embankments, unreinforced andreinforced with geocell were performed to study the impact of geocell on the strengthand stability of confined ballast. Three test configurations (unreinforced, single-layer,double-layer) were used, each of which was loaded to failure under monotonicconditions, and separately loaded cyclically with stress amplitude of 140 kPa and275kPa for unreinforced and reinforced configurations, respectively. Measurementsshow that the presence of geocell allowed for a significant increase in stiffness andstrength while reducing permanent deformation implying that an optimized use ofgeocell reinforcement could lead to significant reduction in maintenance due toballast degradation.
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