A real time interpretation methodology for large scale (2 m**3) in situ rock shear test

A methodology is described for a large scale (2 m**3) in situ rock shear test, taking advantage of real time interpretation. Pressure is transmitted by two flat jacks of 2 m**2 surface each, producing loads over 18 mn. Displacements are measured with a prediction better than 10-**5 m. The pressure and displacement data are interpreted in real time by means of a portable computer, and the results are used to define the next increases of normal and shear pressure. The early detection of plastification allows the determination of intrinsic resistance with a single test specimen. Test results are related to the rock mass by means of a microseismic elastic survey.