Mechanical Properties and Acoustic Emission Characteristics of Weakly Cemented Sandstone With Different Grain Sizes

The weakly cemented sandstone is widely distributed in the Western Mining Area, which mainly formed by mineral grains and minerals through compaction cementation. To study influence of grain size on mechanical properties acoustic emission (AE) characteristics sandstone, uniaxial compression Brazilian splitting AE tests were carried out four specimens with different sizes. physical properties, behaviors, under two conditions analyzed, microfailure mechanism was investigated. results show that P-wave velocity, density, compressive strength (UCS), tensile sandstones sizes decrease increase size. medium coarse exhibit ductile failure, while siltstone fine brittle failure conditions. distribution signal nearly Gaussian time domain. peak frequency upper limit are negatively correlated size, occurrences lots high-strength signals can be used as precursor failure. damage evolution shows trend low-speed damage-accelerated damage-low-speed damage, at load related to tension-shear mixed dominated few shear failures. proportion cracks positively compression, there no significant correlation between splitting.