The creep model based on nonlinear Newton body under different temperature conditions

Mastering the creep deformation characteristics of rock under different temperature conditions is of great significance for studying the long-term stability and deformation mechanism of geotechnical engineering. Based on the classical Burgers model, the creep model under different temperature conditions is established by introducing a nonlinear Newton body. The parameters of the creep model are identified and the influence law of different parameters on rock creep deformation is analyzed. The relationship between model parameters and temperature is quantitatively expressed. The results show that the newly established model can describe the characteristics of the rock in the decay creep stage and the constant creep stage, especially can quantitatively characterize the relationship between the strain and the time of the rock in the tertiary creep under different temperatures conditions. The model fitting curve is highly consistent with the test data, and the correlation coefficient R(2) is above 0.98, which thoroughly verifies the accuracy and rationality of the model. It is found that when the temperature is constant, the creep increases with the increase of the shear modulus of the elastomer G(1), the shear modulus of the viscoelastic body G(2), and the viscosity coefficient of the viscous body η(1) in the constant creep stage. The decay creep property of rock is more obvious with the increase of the viscosity coefficient η(2), and the axial strain tends to a constant value. The achievement can be used to predict the deformation trend of geotechnical engineering with time under different temperature conditions and provide the theoretical basis for long-term stability analysis.