ABSTRACT

The paper presents the results of a recent study on the application of CPTU on soft sensitive Finnish clays. An extensive field and laboratory investigation program was carried out, including 9 test sites of which 5 were studied in more detail. In each of the test sites, a minimum of 4 CPTU soundings, 2-3 field vane test with a new type of down hole vane, sampling with a newly developed large diameter tube sampler and an extensive laboratory investigation program were carried out. Transformation models were developed to estimate the undrained shear strength, preconsolidation stress, and constrained modulus for the over consolidated region. In addition, new information about anisotropy of Finnish clays were obtained. In general, the CPTU tests proved to be very reliable with very good repeatability. However, the measurement of sleeve friction proved to be somewhat problematic for the very soft and sensitive clays studied.