Medusa DMT

The Medusa DMT is able to conduct DMT tests without the need for a control unit, nitrogen bottles, gas tubes and operator control of pressure. It has a downhole system that uses an electric motor to apply hydraulic pressure to the DMT blade.  The downhole unit is controlled via a CPT cable connected to a laptop that has simple and easy to use software.  The process of inflating and deflating the DMT is controlled by the software, removing potential sources of error from operator control of the pressure.

The major advantages of the Medusa DMT are: 

1. Less equipment, no control unit, nitrogen bottles or gas tubes.

2. It can operate in cableless mode, which can be useful for offshore work.

3. The pressure is generated and measured locally at the test depth, which removes problems of pressure equalisation along pneumatic cables.

4. The pressure control of the DMT is independent of the operator. The automatic control of pressure is highly repeatable and provides the correct timing to obtain the A and B pressure readings, in accordance with international standards or any other required timing.

5. The capability of the Medusa DMT of measuring (virtually continuously) the total horizontal pressure against the membrane with time enables new research possibilities.

6. Short A-dissipations, consisting of repeated A-readings (without expansion of the membrane from A to B) for a couple of minutes, may be executed to detect intermediate or partially draining soil layers (Marchetti 2015, Marchetti and Monaco 2018).

 More information is available from the Marchetti website - https://www.marchetti-dmt.it/instruments/medusa/