Nature of Quickclays

Abstract

THE strength of clay soils in situ is often greater than the disturbed or remoulded strength and the ratio of these two values is a measure of the “sensitivity” of the soil; this may vary from ∼ 1 for a London clay to ∼ 1,500 for a Canadian Leda clay¹. The extremely sensitive soils, known as quickclays, are chiefly found in northern North America and Scandinavia, and they present a considerable geotechnical hazard because of a tendency to failure by landslide. The loss of strength at failure is remarkable—the material changes from a strong brittle soil into a viscous liquid, and this has proved difficult to explain.