EVOLVEMENT LAW OF ROCK AND WATER COUPLING PARAMETERS DURING THE FAILURE PROCESSES

On the bases of the theoretical analyses, the mechanical model of rock and water interaction is established, and the formula of coupling mechanical parameters between rock and water interaction is deduced. It is proved that the scope of Biot coefficient is between the initial porosity and 1. A new determination method for the yield stress by the virtue of non-drainage test is proposed, which is based on such tests as grouting tests at different deviatoric stress states, non-drainage tests, tests with water pressure change under non-drainage, and proportional loading tests under non-drainage, etc. The evolvement of coupling mechanical parameters is observed during the rock failure process. The water pressure decreases the failure strength of rock, but increases its deformation. Laboratory tests demonstrate the large scattering of Skempton coefficient. The mechanism of water pressure under grouting water is different with that under drainage. The Biot coefficient in axial direction has different evolvement law with that in radial direction. This research is very important in the field of oil exploit and high radioactive nuclear waste material deposit.