Experimental investigation of the mechanical properties of mudstone in southwestern China

In this paper the mechanical properties of mudstone with different immersion durations (e.g., immersion in water for 0, 7 and 14 days), at different temperatures (20, 35 and 50 °C) and in different confining pressures (0.6 and 1.2 MPa) were investigated using uniaxial compression tests, conventional triaxial compression tests and scanning electron microscopy. The test results indicate that in the temperature range from 20 °C to 50 °C the water content can significantly reduce the mechanical parameters, including the strength and elastic modulus of the mudstone samples. In contrast, the Poisson ratio of the mudstone samples increases with the increase in the water content. In addition, there is little difference between the effects of an immersion time of 7 days and 14 days on the mudstone samples, indicating that the confining pressure plays a protective role on the mudstone samples.