Abstract:Aimed at viscoelastic deformation prediction in rock engineering,an incremental formula of relative displacement is deduced based on Goursat expression of elastic displacement and elasticity-viscoelasticity analogy principle,and a deformation predicting model with methods and steps is proposed. It does not need the true values of time,boundary condition and physical property parameters of the rock mass,but obtains a group of combination values. The proposed method considering constitutive character of the rock mass can predict two-dimensional long-term deformation without stress and displacement boundary conditions. Then,it is applied to slope engineering,in which the comparison between predicted and measured deformation indicates that the method has high short-term prediction precision with error smaller than 10%,while the error is about 23% in the long-term prediction. At last,the engineering applicability of the method is discussed by an example of slope excavation which provides theoretical foundation and practical method for predicting two-dimensional long-term visco-elastic deformation of rock engineering.