Nonlinear Creep Damage Constitutive Model of Rock
JIANG Yu-zhou
XU Wei-ya
WANG Rui-hong
WANG Wei
Abstract：Three stages of mechanical creep in rock were studied. There is nonlinear hardening during primary and steady-state creep. During these stages intrinsic damage to the rock is im-material and may be neglected. During accelerated creep intrinsic damage becomes continuous and exacerbates the nonlinear characteristic of the response. The intrinsic damage to the rock is assumed to be exponential in time and stress level during accelerated creep. A damage evolution equation is proposed. Nonlinear hardening and damage are introduced into the Maxwell consti-tutive creep model. This proposed model can better describe the three typical stages of nonlin-ear creep in rock. Creep experiments were preformed on sandstone taken from the right bank, underground powerhouse of the Xiangjiaba hydro-power project. A servo-controlled rheology testing machine was used for these tests, which determined the tri-axial accelerated creep curves of the rock. Creep parameters for the proposed model are identified from the data. The fit model agrees well with the test creep data.
Keywords：rock mechanicsdamagecreep modelsandstonenonlinear
Publication Date：2009-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：5( 331-335 )