Research On Sandstone Creep Rupture And The Water Fluid-solid Coupling Experiment

The destruction of rock mass under long-term load is often caused by creep aging gradual damage dominant role. Creep causes the change of porosity of rock mass, as a consequence of causing the dramatic change of permeability characteristics;in turn, the change of permeability characteristics cause the change of seepage field, leading to the change of characteristic parameters of rock mass creep. Therefore, the creep and seepage are coupled to each other. This article through the theoretical research,experimental research and model building methods such as creep damage rule of sandstone and the influence law of groundwater on the creep damage of sandstone was analyzed, the main research content is as follows:①Through TAW-2000 electro-hydraulic servo rock triaxial testing machine, using hierarchical load method for rock triaxial compression creep experiment, the experiment of acquired information, integrate and research for the same in different confining pressure and water pressure, water pressure and confining pressure condition, in turn,get same time varying strength curve and deformation time curve, unloading confining pressure creep deformation curve. Analysis of the rule of the creep rupture of sandstone and creep coupling of seepage water of sandstone are studied. Conclusion: through the experiment is relationship between confining pressure and time varying strength, with inverse association between creep variable; Exist when the water pressure, the time-varying of the rock strength is reduced, creep variable increases, and the water pressure, the greater the time varying strength is smaller, creep variable within a certain range increased; Unloading confining pressure creep damage time shorter, its creep variable also appeared to reduce; Rock mass within a dynamic balance of fluid-solid coupling seepage system, and the destruction of groundwater can obviously accelerate the dynamic equilibrium. The permeability coefficient of the specimens and positive correlation relationship between volume strain.②According to the creep characteristics of sandstone, on the basis of predecessors’ research to build the nonlinear creep model of sandstone, build components selected according to the experimental creep curve, creep formula for creep model related with the constitutive equation, and then how to clearly illustrates the model parameters.③ Using the ansys finite element numerical simulation software to establish nonlinear creep model, simulation test by means of hierarchical load conditions, throughthe analysis of the numerical simulation of displacement nephogram, the basic consistent with the test process.