Studio Prof. Marchetti S.r.l. is the manufacturing company of the Marchetti Flat Dilatometer (DMT), the Seismic Dilatometer (SDMT) and other innovative equipment for onshore, nearshore and offshore soil investigation.
Flat Dilatometer (DMT):
The Flat Dilatometer (DMT) is an in-situ test for the determination of various key soil parameters used for geotechnical design. The test is rapid, accurate, simple and cost-effective. The results are highly repeatable and independent from the operator. The blade may be advanced with any field machine, including penetrometers and drill rigs. DMT measurements are performed in situ, directly on the soil in its original position and state. This eliminates the disturbance caused by drilling, sampling, and transport to laboratory. The profiles of the results are available real time during test execution. The direct measurement of soil deformation enables accurate estimations of the elastic modulus. The KD parameter provides stress history information of the soil, a very difficult property to assess with other testing methods.
Main Applications
- Soil stratigraphy
- Stress history (OCR, K0)
- Settlement prediction
- Soil Improvement quantification
- Slip surface detection in clayey slopes
- P-y curves for laterally loaded piles
- Liquefaction potential
- Permeability in clay
- FEM input parameters (ex. Plaxis)
- Subgrade modulus for pavements
- Subgrade modulus for diaphragm walls
Seismic Dilatometer (SDMT):
The Seismic Dilatometer (SDMT) is a probe for measuring the shear wave velocity Vs. The test provides accurate and repeatable results with a rapid, reliable and simple technology which does not require any geophysical background. The True Interval configuration is implemented with two sensors spaced 0.5 m. The electronic board provides very accurate AD signal conversion and uses digital data transmission. The high quality of the acquired seismograms enables real time shear wave velocity evaluation. The Vs profiles are available up to the current test depth. Accelerometers monitor the inclination of the SDMT probe during penetration. The SPDMT is an enhanced version of the Seismic Dilatometer containing two additional sensors for recording compression P waves.
Main Applications
- Max Shear Modulus G0
- In situ G-gamma decay curve
- Sample Quality Assessment
- Local Seismic Response
- Soil category (Vs30)
Medusa DMT
The Medusa DMT is an automated dilatometer probe able to autonomously perform the test. An electronic board, powered with rechargeable batteries, activates a motorized syringe for expanding hydraulically the DMT membrane. The blade has the same dimensions of the original standard flat plate dilatometer. The device may operate without any cable (MEMO mode) or with an electric cable for real time results.
Offshore Testing
Studio Prof. Marchetti has directed several world-wide offshore projects for performing DMT and SDMT measurements from the floors of rivers, lakes and seas. The know-how based on many years of experience has made the execution of such tests reliable, robust and efficient. A key step consists in determining the most cost-effective setup ensuring correct test execution. Shear wave velocity measurements are performed with a custom designed seafloor hammer.
