Design parameters of Portuguese granitic residual soils obtained from DMT tests

: Cemented soils are often seen as non-textbook materials, since they donŽt fit into the usual behavior of transportedsoils in the light of classical Soil Mechanics theories. This fact creates several problems on the interpretation of in-situtest results, when the classical approaches are used, limiting the application of common in-situ tests. Departing from a longexperience in characterizing Portuguese granitic soils with Marchettis Dilatometer (DMT) a large calibration box (CemSoilBox) was constructed to work with artificially cemented silty sands, aiming the evaluation of static penetration influence in theloss of cementation strength, and the overall effects on the stiffness response, giving rise to adequate correlations for derivingdesign parameters. The experience was based in the development of artificially samples tested in triaxial cell and in the CemSoilBox, where blades could be pre-installed and pushed in. Water level, suction and seismic velocities were monitored during theexperience. The final results allowed for the establishment of specific correlations to derive strength (cohesion intercept andangles of shearing resistance) and stiffness (deformability and small strain shear modulus) parameters, as well as a specificmethodology for controlling suction influence on the respective results