Geology and engineering properties of Connecticut Valley Varved Clay

摘要

This paper describes the geology and geotechnical engineering properties of Connecticut Valley Varved Clay (CVVC). Results from soil sampling, in situ testing, and laboratory testing conducted during the past 10 years for a deposit of CWC at the National Geotechnical Experimentation Site in Amherst, Massachusetts, USA are presented. CWC is a lacustrine soil deposited approximately 15,000 years ago during retreat of the Laurentide Ice Sheet. The soil's most distinguishing feature is its varved nature with alternating layers of silt and clay. This gives CWC several unique engineering properties making it a challenging soil for engineering design. CWC has hydraulic conductivity and undrained shear strength anisotropy that far exceeds that of most other soils. The strength of the soil for shearing along the horizontal varves is much less than that for shearing across the varves. The paper presents data on these and other soil classification, index, and engineering properties based on in situ measurements and laboratory test results.