Permeability and stability of base and subbase materials : research implementation plan.

664678808Research implementation plan.PDFTech ReportFHWA-OH 2000/01714512Subgrade materialsPermeabilitySoils by permeabilityOhioUniversity of Toledo. Dept. of Civil EngineeringRandolph, Brian W.Heydinger, Andrew G.Gupta, Jiwan D.University of Toledo. Dept. of Civil EngineeringOhio. Dept. of TransportationUnited States. Federal Highway AdministrationNTL-HIGHWAY/ROAD TRANSPORTATION-Soils and GeologyNTL-HIGHWAY/ROAD TRANSPORTATION-Pavement Management and PerformanceUS Transportation CollectionThe purpose of pavement base and subbase courses is to provide a means for free water to drain frombeneath roadways while providing structural support for the pavement. Problems occur when highwaymaterials which are assumed to have adequate drainage characteristics actually have low permeabilityand low effective porosity.It has been observed that some base and subbase materials meeting the gradation requirements provideonly fair to poor drainage characteristics. The current gradation ranges permit a broad range of possiblepermeability and effective porosities. It is necessary to investigate bases and subbases that satisfy thecurrent gradation specifications to determine ranges of their permeability and effective porosities