The Rheological Combination Model Describing Accelerated Creep And The Creep Experiments Research Of Rocks And Coal

In the rock and soil, there are a number of time-dependent phenomena. If the time influence on rock and soil is neglected, a great disparity is caused between predicting data and in-situ measures and thus may impact on the criteria for selection of the proper design. And the time-dependent mechanical behaviors are fundamental mechanical properties of rock and soil.Because of this, a proper creep constitutive equation is very important. The methods of deducing the material constitutive equation include the theory of component model, empirical equations, and so on. The author uses the method of the component model to work out the rheological constitutive equation. Model components include elastic substance and plastic one and viscous one. Generally, the viscosity of the rock is seen to follow Newton viscous law. Actually, the rock possesses the properties of non-Newton fluid. The author puts forward a non-Newton substance, with which the author constitutes a combination model. And a lot of uniaxial and triaxial creep experiments are done by Instron-1346 electric-hydraulic serving compression machine. And the method is adopted of a multi-level loading mode on a single specimen. The experimental curves agree with the typical rheological ones. According to experimental data and the minimum quadric multiplication, the parameters of the combination model are calculated. And the theorical curves are painted. Theorical figures are identical to the experimental ones. The author draws the isochrous curves and rheological velocity-time ones and analyses mechanical behavior of rocks and coal in the creep procedure.