Foundation Precompression with Vertical Sand Drains

by Stanley J. Johnson, (F.ASCE), Spec. Asst.; Soils Div., U.S. Army Engrs. Waterways Exper. Sta., Vicksburg, MI,

Serial Information: Journal of the Soil Mechanics and Foundations Division, 1970, Vol. 96, Issue 1, Pg. 145-175

Document Type: Journal Paper


Foundation precompression through use of preload fills combined with vertical sand drains to accelerate consolidation is described with reference to uses, design procedures, and possible effects of alternative methods for installing vertical sand drains. Vertical sand drains to accelerate consolidation are probably not required where soils contain continuous intermediate sand layers within the compressible stratum, but pressure-relief wells may be required to reduce excess pore-water pressures in the sand layers. The pressure-relief wells can be sand drains, free-flowing wellpoints, or conventional wells. Also, vertical sand drains will probably serve no purpose where design loadings will not exceed preconsolidation stresses. Field tests may be required in some stratified materials to evaluate the efficacy of thin pervious soils as drainage layers. The importance of designing for secondary compression effects is emphasized.

Subject Headings: Consolidated soils | Soil pressure | Soil compression | Drainage | Layered soils | Foundation design | Foundations | Sandy soils

Services: Buy this book/Buy this article


Return to search