Consolidation property is an indicator of load bearing capacity of foundation and also reflects the process of geological evolution. In general, consolidation test has been performed for soil materials in geotechnical area, however we tried to conduct consolidation test using Mio–Pleistocene sedimentary rocks taken from a forearc basin located at a subduction zone. Consolidation yield stress almost increased as porosity decreases, however consolidation yield stress has variation in same porosity and it was increased with depth of sampling point, that indicates the consolidation line of this setting and the consolidation yield stress would record the maximum burial depth of the basin. SEM images show the consolidation fabric which has layer structure and high-resolution X-ray CT images show a deformation during the consolidation test.
Consolidation property is one of the important mechanical properties of sedimentary rocks both in geoengineering and geologic fields. It is an indicator of load bearing capacity of foundation and also reflects the process of geological evolution. In general, consolidation test has been performed for soil materials in geotechnical area to examine the state of underground which is basement of building and to clarify the process of consolidation. Although the test may also be used for soft sedimentary rocks to investigate the tectonic process, e.g. the developmental process of the plate boundary where the crustal movement is violent (Morgan & Ask 2004), only a few such previous researches are available.
To examine the excess pore pressure induced by the marine landslide, the one-dimensional consolidation tests were performed and the consolidation yield stress were estimated using a Pliocene sedimentary rock with around 40% porosity taken from a forearc basin located at a subduction zone (Kamiya et al., 2018). In this study, we report the properties in detail during the consolidation tests using a constant strain-rate loading system and discuss the results of the consolidation tests with the observation of the micro fabric and the consolidation deformation using SEM and X-ray CT images.
