Abstract:

Based on the equipment ofMTS, the wave velocity and mechanical parameters of sands and mudstones from northeast of Sichuan are taken into synchronous experimentation under the condition of simulated formation. The varying regular pattern and the relationship between dynamic and quiescent parameters on the vertical formation are discussed. Under the condition of simulated formation, in terrestrial formation, the average compressive strength value of sand is 241.87 MPa, and it is 115.63 MPa of the mudstone. The average elastic modulus value of sand is 35.5 GPa, and it is 24.8 GPa of the mudstone. The average poisson ratio value of sand is 0.27, and it is 0.33 of the mudstone. The average cohesion value of sand is 29.32 MPa, and it is 10.11 MPa of the mudstone. The average internal frictional angle value of sand is 36.1 , and it is 19 of the mudstone. The relationship of tensile strength on the terrestrial formation is J₂z>T₃x>J₂s>J₂q, and the average value of tensile strength is 7.09MPa, 6.2MPa, 4.72MPa, 4.51MPa. The value of rock mechanic parameters is affected by the grain size, shale content, binding material’s property and the porosity. After being saturated bywater, the longitudinal velocity, elastic modulus and the poisson ration is increased remarkably than before. With the broadening of confinement pressure, the plastic deformation proportion is increasing, and the distortional character is displaying to elastic-plastic deformation more.

Key words: tuffaceous sandstone, conduction mechanism, water saturation model, Wuerxun Sag