In situ testing
Double Flat Jack
In situ stress measurements
In situ testing
Measurements and monitoring
Software
The Double Flat Jack test is used to measure the elastic modulus.When the material is weak (low strength), pushing the test until rupture, a measurement of the uniaxial compression strength is obtained.
Usually this test is carried out after a stress measurement by single flat jack. Inserting a second jack at a distance about equal to the flat jack width.
Typical application scopes are tunnel walls, quarries and underground exploitations of ornamental stones, the body of concrete dams, masonry walls of historical buildings..
Depending on the size of the structure to be investigated, several shapes and sizes are available.
The equipment and the experimental / interpretative procedures that we use are suitable for a wide range of situations:
- the cuts are executed by means of a diamond saw up to the depth 260 mm, with thickness 4 mm;
- the flat jack pressure can reach 20 MPa.