Time-dependent Behavior of Rocks

Publisher Summary Time-dependent deformation is continued deformation without a stress change. Creep strain seldom can be recovered fully when loads are removed, thus it is largely plastic deformation, Rarely, primary creep strain may be recovered without fabric damage when stresses are returned to their original state. All rocks creep upon undergoing a load change. Commonly it terminates in a few minutes or hours, or is so small that it can be ignored in design. Most rocks creep appreciably only at T and [σ] values not encountered in engineering structures. Creep and rupture are issues in cases of high point loads, aggressive water chemistry, or tensile stresses that lead to time-dependent fracture growth. These cases may be difficult to simulate in the laboratory, and field quantification may be challenging.