Study On The Stress-strain Relatinship Of Argillaceous Sandstone And Its Strength Properties

The author analysed argillaceous sandstone's physical properties and chemical properties, carried out the uniaxial compression tests and the triaxial compression tests on argillaceous sandstone,in which, the loading direction are parallel and vertical to the bedding of rock sample respectively, and found all of the stress-strain curves possess strain softening. The strengths of sandsone from uniaxial compression tests, in which the loading direction are parallel to the bedding of rock sample,are less than that the loading direction being vertical to the bedding of rock sample. Argillaceous sandstone becomes soften greatly when it meet water,the relationship between the strength of uniaxial compression and water content possesses exponent form. The strength of the sample disturbed by blasting is 38% of that of sample undisturbed.elastic modulus of the sample disturbed by blasting is 30% of that of sample undisturbed.The cohesion and inner friction angle for loading direction being vertical to the bedding of rock sample are greater than that of loading direction being parallel to the bedding of rock sample. Water content affect cohesion apparently, does not affect inner angle almost. Using modified Duncan-Zhang model, the author computed the stress-strain of the sandstone, which agree with the result from the triaxial compression tests,and tried to investigate symmetry constitutive relationship of sandstone in the method set forward by the author. Finally, the ANSYS program is applied to simulate the process of excavating and supportting a tunnel located in Jingbian county in the Shaanxi Province.