Experimental study on mechanical characteristics and microscopic mechanism of white sandstone in northern Xinjiang
In order to analyze the mechanical properties of white sandstone in northern Xinjiang,the direct shear,compression,permeability and SEM tests of white sandstone under different factors were carried out to analyze the mechanical properties from the macro and micro perspectives and reveal its microscopic mechanism.The test results show that in the direct shear test,the cohesion changes parabolically with the increase of moisture content,reaching a peak near the optimal moisture content,the internal friction angle decreases linearly with the increase of moisture content,and the cohesion and internal friction angle both show a linear upward trend with the increase of dry density.In the compression test,the compression index gradually increases and the rebound index fluctuates with the increase of moisture content,the compression index and rebound index decrease exponentially with the increase of dry density,the particle size increases and the roundness,pore size and microscopic porosity decrease with the increase of vertical pressure,the particles and pores have obvious orientation,and the microscopic porosity is the main factor affecting the compression index.In the permeability test,the permeability coefficient decreases exponentially with the increase of dry density,the magnitude of permeability coefficient decreases from 10-4 to 10-6 when the dry density increases from 1.60 g/cm3to 1.84 g/cm3,the trellis pore and permeability decrease with the increase of dry density,there is a significant correlation between the average pore size and permeability coefficient,and the average pore size is the key factor influencing the permeability of white sandstone.
white sandstoneshear characteristicscompression characteristicspermeabilitymicroscopic mechanismnorthern Xinjiang
万方数据
维普
