Theoretical and experimental study on time-temperature equivalent principle for rock

Based on the theory of irreversible process thermodynamics in part I of this paper, non-linear thermodynamic analysis is engaged in , and non-linear stress-strain-temperature equations are established. Thus, general expression for time-temperature equivalent principle is theoretically obtained. And furthermore in part II, the equation of displacement facto in time-temperature equivalent principle is derived. At last, the parameters in the equation are determined, and the main curves for creep compliance and cohesive of three Gorges granite are obtained by a series of tests. As a result, it is proved that both deformation and strength performances obey the principle.