On compression characteristics of Ariake clays

J.B. Burland proposed that the void index aids in assessing the compressibility of various sedimentary clays. The extensive data on sensitive Ariake clays are used in this study to investigate the compression behavior using the void index. The analysis results indicate that the compression curves of remolded Ariake clays can be normalized by the void index proposed by Burland. It is found, however, that most natural Ariake clays lie above the sedimentation compression line. Salt removal and cementation are considered to be the most probable causes for such a phenomenon for Ariake clays. Furthermore, a relatively good relationship is found between the in situ void ratio of Ariake clays and the effective overburden pressure. The relationship can be expressed by a straight line in a bilogarithmic plot, herein designated field state line (FSL) for Ariake clays.