Compressibility of a Certain Volcanic Clay

Abstract

The settlement of buildings resting on a volcanic clay, known as Kanto loam, shows particular behavior which is quite different from that of sedimentary saturated clay. The authors have been observing for about eight years the actual settlement of buildings built on the Kanto loam. The Kanto loam is a very porous, unsaturated clay. The compression of this clay consists mainly of the initial compression (immediate compression) and the following creep, the consolidation process being practically ignored. This paper deals mainly with an experimental approach to the compressibility of the Kanto loam. Long term compression tests were made and rate of the creep was observed. It has been found from these tests that both the volumetric creep and the shearing creep exist and they proceed straightly against the logarithm of the elapsed time. Comparison has been also made between the observed and calculated settlement, and the result shows a fairly satisfactory agreement.