Accelerated Testing on Separation Layers for Open-Graded Drainage Layers

摘要

An accelerated testing procedure was developed to evaluate performance ofseparation layers used between open-graded bases and lime stabilized subgrades. A principal concern was assessing separation layer performance in regard to the degree of pumping into the open-graded base and the magnitude of deformations occurring during testing. A pneumatically driven, electronically controlled, repeated loading laboratory apparatus was designed and constructed to perform the testing of these materials. A low plasticity clay and a silty clay till soil were tested in this research. The separation layer investigated included non-woven geotextiles and a dense-graded base aggregate blend. specimens were housed in a stiff wall plexiglas cylinder during testing. Tests were conducted at various loading levels and durations in order to develop the accelerated testing procedure.