Variability of an Auckland residual soil profile obtained from closely spaced CPT soundings

A total of 29 CPT soundings up to depths approaching 10 m were made at close spacings, so that an intensive exploration was made of the properties of a limited volume of residual soil in the Albany area of Auckland. Since the soil was derived from in situ weathering of Waitemata group sandstones and siltstones, the properties are expected to vary in the vertical direction (this was indeed found to be the case) so the variations between the properties at each level were investigated. The underlying hypothesis of the work was that in situ weathering produces soil that has significant point to point variability. The interpretation of the data obtained would seem to support this concept.