STRUCTURAL HIERARCHY AND MECHANICAL PROPERTIES OF ROCK MASS. Part Ⅱ: STRUCTURAL HIERARCHY AND STRENGTH

摘要

The concept of structural hierarchy of rock mass opens a new way to interpretation of size effect. Analysis based on this concept shows that size effect may be attributed to the existence of structural hierarchy of rock mass. Analysis in this paper demonstrates that strain rate sensitivity of strength of rock mass may be looked at as the result of competition between the coexisting thermo-activation and macro-viscous mechanisms,which dominate in different diapasons of strain rate. Comparison with the experimental data shows as suggested in this paper, that the model describes very well strain rate sensitivity of strength of rock mass in wide diapason of strain rate ranging from low to high strain rate.