Contribution of triaxial test for rock poroelastic properties evaluation(Conference Paper)

In the scope of mining and petroleum engineering and to some extend of civil engineering, rock properties are relevant for the design of safe underground cavities, for hydraulic fracturing control, for rock masses stabilization and rock blasting operations. For petroleum engineering, porosity and permeability are associated with production and hydrocarbon reservoirs recovery. In what concerns the environmental restoration and waste disposal the poroelastic properties are also relevant for its safe management. The objective of this work is to evaluate the variation of stress state, in the poroelastic properties of rocks, due to several anthropogenic activities in engineering and science fields. In this study, variations on strain paths, porosity, permeability, P-wave velocities in triaxial tests over a set of microbialite limestone specimens were observed. Triaxial compression tests for three different conditions of confining pressure and injection of water pressure (50 and 100 kPa) were executed. The results highlighted that all the poroelastic properties depends not only on the axial stress and injection of water pressure but mostly due to confining pressure. It was also observed the poroelastic properties variation during the different phases described on Bieniawski brittle mechanism of rupture. © SGEM 2014.