ENGINEERING CHARACTERISTICS OF BRITISH OVER-CONSOLIDATED CLAYS AND MUDROCKS .1. TERTIARY DEPOSITS

There is much information in the literature relating to the classification, strength, deformability, permeability and other geotechnical properties displayed by British overconsolidated clays and mudrocks. The opportunity has been taken in this paper to collate published values of the more important geotechnical parameters for a number of Tertiary formations and to present ranges and averages in a convenient form. Since the degree of weathering is particularly important, values for both weathered and unweathered materials are presented where possible. Mineralogical composition, geological loading, present burial depth and method of testing are also significant causes of variation. Some implications regarding the choice of design parameters are discussed; of particular relevance is the degree and orientation of fissuring present.