Constrained modulus MDMT is defined as the vertical drained confined tangent modulus at σvo. Modulus MDMT is obtained from dilatometric tests (DMT).
If the value of the constrained modulus MDMT is not available, it is possible to input the coefficient of volume compressibility mV (determined from the oedometric test) and the program carries out the respective transformation: transformation:
where: | MDMT | - | constrained modulus |
mV | - | coefficient of volume compressibility |
The analysis employs the constrained modulus MDMT or coefficient of volume compressibility mV and is based on Marchetti's theory. This approach is based on linear elasticity, provides a settlement proportional to the load, and is unable to provide non-linear predictions.
The settlement of the ith layer is then provided by:
where: | σz,i | - | vertical component of incremental stress in the middle of ith layer |
hi | - | thickness of the ith layer | |
MDMT | - | constrained modulus |
Literature:
Marchetti, S., Monaco, P., Totani, G. & Calabrese, M.: The Flat Dilatometric Test (DMT) in soil investigations. A Report by the ISSMGE Committee TC16, University of L'Aquila, Italy, 2001, 48 p.
https://www.finesoftware.eu/help/geo5/en/settlement-analysis-using-dmt-constrained-soil-modulus-01/
The DilatoMetric Test (DMT) is performed by using a dilatometric, which operates on the principle of verification of values by using the displacements of the inductive sensors (with a sensitivity of up to 0.001 mm). The advantage of these tests is a more accurate description of the displacement and deformation of foundation soil.
The results of the dilatometric test (DMT) are imported into
the program by inserting the file in format UNI (*.uni). It is a standardized and universal format for import of the measured data obtained from
dilatometric tests, which is used in the world.
The name of the test and the depth of the first point of the
DMT is entered in the "New field test" dialog window. In the "Stratigraphy" program, the input of coordinations x, y, z is required.
The constrained
soil modulus MDMT is entered in the table.
Reference:
Literature:
Marchetti,
S., Monaco, P., Totani, G. & Calabrese, M.: The Flat Dilatometer Test (DMT)
in soil investigations. A Report by the ISSMGE Committee TC16, University of
L'Aquila, Italy, 2001, 48 p.
Roy
E. Hunt: Geotechnical Engineering Investigation Handbook, Second Edition (CRC
Press, 2005)
EN
ISO 22476-11: Geotechnical investigation and testing - Field testing. Part 11:
Flat dilatometer test
https://www.finesoftware.eu/help/geo5/en/dilatometric-test-dmt-01/