Application of Damage Mechanics to Deep Tunnels
The paper utilizes an anisotropic nonlinear damage model in strain space to describe the behavior of jointed rock and applies it to mechanical analysis of tunneling. This work focuses on rate-independent and small-deformation behavior during static isothermal processes. The prime results include: (1) the properties of damage-dependent elasticity tensors based on geological information of the jointed rock mass; (2) the damage evolution law presented on the basis of thermodynamics and combined with the endochronic theory; (3) the symmetric form of the effective stress concept which held between the elasticity tensor of the damaged material and that of the fictitious undamaged material; and (4) the global damage tensor based on the work-equivalence principle and the local geological data of multi-joint sets. Finally the numerical results of a tunnel intersection in jointed rock is presented to illustrate the mechanical behavior of this model.
KeywordsRock Mass Damage Evolution Jointed Rock Elasticity Tensor Jointed Rock Mass
Unable to display preview. Download preview PDF.
- KACHANOV L.M. (1958). Time of the rupture process under creep condition, IVZ Akad Nauk, S.S.R., Otd Tech Nauk, 8: 26–31.Google Scholar
- LEMAITRE J. (1990). A Course on Damage Mechanics. 2nd Edition, Springer, Berlin.Google Scholar
- MALVERN L.E. (1969). Introduction to the mechanics of a continuous medium. Prentice-Hall, Inc., Englewood Cliffs, N.J.Google Scholar
- MURAKAMI S. & N. OHNO (1980). A continuum theory of creep and creep damage. Proc. 3rd IUTAM Symp. on Creep in Structures, Ponter, A. R. S. and Hayhust, D. R. Ed., Springer-Verlag, Berlin, 422–443.Google Scholar
- STUMVOLL M. & G. SWOBODA (1993). Deformation behaviour of ductile solids containing anisotropic damage. J. Engng. Mech., ASCE, 19: 1321–1332.Google Scholar
- SWOBODA G., Q. YANG & F. ITO (1995). Damage propagation model and its application to rock engineering. Proc. 8th Int. Congress on Rock Engineering, Tokyo, 159–163.Google Scholar