Standards: NF P 94-110-1, NF EN ISO 22476-4, ISO 22476-4, ASTM D4719-0
Pressuremeter test is a lateral loading in-situ test and used to determine the engineering characteristics of soil and/or rocks.
The probe of the pressuremeter is inserted into the borehole and is supported at test depth.
The probe is an inflatable flexible membrane which applies even pressure to the walls of the borehole as it expands.
As the pressure increases and the membrane expands, the walls of the borehole begin to deform.
The pressure inside the probe is held constant for a specific period of time and the increase in volume required to maintain the pressure is recorded.
There are two types of tests that can be performed with the pressuremeter.
The stress controlled test increases pressure in equal increments while the strain controlled test increases the volume in equal increments.
The Menard manual pressuremeters (Control Unit) with their accessories and in particular tubings and 3-cells probe to perform in situ Pressuremeter test in soil (static loading test of the soil in place). From the test reading (volume variation based on controlled pressure), a stress-strain curve can be obtained, in the case of plane deformation, which yields :
the Ménard Pressuremeter modulus, Em
the creep pressure Pf
the Ménard limit pressure Pl.
Two models of manual pressuremeters are available:
Standard Menard Pressuremeter - 100 bar capacity
The device is composed of a Control Unit allowing to regulate with precision the pressure in the probe in order to carry out the static loading of the soil in place and to follow the evolution of the loading stages, the whole being connected by high resistance tubings.
Menard VHP (Very High Pressure) Pressuremeter - 140 bar capacity
In addition to the standard device, it is composed of a specific high-pressure main regulator and internal copper tubing with a working pressure of over 200 bar. Its sight glass can be removed as a precaution, the test being controlled only with the recorder.
THE BENEFITS
Conception following the original Ménard procedures
Clear and easy to use control panel principles
Easy to read measurements
Quality tripod: robust, stable and easy to install
Simply general maintenance with special package
APPLICATIONS
In situ stress controlled loading test performed on the wall of a borehole using a cylindrical probe which can expand radially.
DATA ACQUISITION SYSTEM
The GeoSPAD®2 system, consisting of sensors and a recording and communication box with GeoBOX®, is integrated with the Menard Pressuremeter for the acquisition of pressuremeter test data via the GeoBOX® universal central unit. This equipment enables the conditions and data of these tests to be recorded automatically, whether they are conventional or, as an option, cyclical (loading/unloading). This system in conjunction with GeoBOX® allows the operator to concentrate on the test without having to record all the data, by controlling the progress of the pressuremeter tests on the GeoBOX® screen and the engineer to save a considerable amount of time by directly loading all the data rather than entering them manually. The GeoSPAD®2 thus avoids the risk of errors, both when taking manual notes on site and when re-entering data on the computer.
This recorded data is transferred via the optional 4G modem or USB key to the GeoVISION®-P data processing software.