Structure and Mechanical Properties of the Dueñas Clay Formation (Tertiary Duero Basin, Spain): An Overconsolidated Clay of Lacustrine Origin

The Dueñas Clay Formation is considered an example of a deposit lacustrine continental origin. It formed mainly by overconsolidated clays and includes feldspathic arenites, clayey silty levels; however, in geotechnical projects it clay unit treated as whole. structure each level was assessed the field, thin sections, SEM case level. In addition, identification, strength, deformation, durability tests were undertaken according to nature samples (grain size analysis, Atterberg Limits, point load test, direct shear tests, uniaxial compression swelling pressure, unidimensional consolidation tests). test used criterion for dividing levels within formation their behavior soil or rock. observed that proportion type carbonate cementation controls way which material behaves, with sparithic cement increasing strength. are expansive due presence smectite, also influences under stress. massive laminar layers caused conditions, addition processes post-sedimentation, explain low compressibility.