Study On The Effect Of Mud Rock Disintegration On Slope Stability In Alpine Area

The Xinjiang region of China is rich in coal resources,and mudstone is one of the main rock types of open-pit coal mine slopes in the Xinjiang region of China.Due to the influence of climate,rainfall and other factors in Xinjiang,the rock mass of the mine has disintegration and freeze-thaw damage,which affects the slope stability coefficient of the open-pit mine and leads to slope instability.The mudstones in the slopes of high and cold areas are affected by the environment and become an important research topic.Therefore,it is of great significance to deeply understand the influencing factors of the disintegration resistance of mudstones for the safe exploitation of mineral resources in the cold regions of Xinjiang.In this paper,taking into account the needs of mine engineering in the cold region,we sampled from the slope of the southern open pit coal mine in Xinjiang,China,and selected the mudstone at the slope of the open pit stope.Using the number of freeze-thaw cycles as the control condition,we studied the two mudstones under different freeze-thaw environments.The mechanical characteristic parameters such as the change of disintegration resistance,compressive strength,cohesion and internal friction angle,and XRD component analysis of the mudstone were combined with the disintegration test to analyze the disintegration mechanism of the mudstone.research shows:(1)Select the mudstone pattern for indoor dry-wet cycle disintegration test.It is found that red sandstone has the strongest resistance to disintegration,while yellow mudstone and pink mudstone have weaker resistance to disintegration.The disintegration mechanism of mudstone is discussed through experimental data combined with component analysis.The disintegration is mainly due to the existence of macro-cracks on the surface of the mudstone,and water can enter into soften or dissolve some cement.The reason for the disintegration of yellow mudstone and pink mudstone is that the clay content is relatively high many.(2)Based on the observation data of climate change in the region throughout the year,freeze-thaw cycle tests were conducted on different mudstones,and it was found that the higher the strength of the mudstones,the less affected by freeze-thaw cycles.In the same mudstone,the more the freeze-thaw cycles of the mudstone,the more obvious the impact.The effect of the freeze-thaw cycle on the compressive strength of the mudstone is greater than the impact of the mudstone disintegration index.(3)Direct shear test was used for mudstones in Xinjiang open-pit mines with different freeze-thaw cycles.The shear strength index cohesion and internal frictionangle of the yellow mudstone and pink mudstone patterns decreased with the increase of freeze-thaw cycles,indicating Freeze-thaw effects affect the shear strength.Up to60 freeze-thaw cycles,the damage intensity of yellow mudstone is lower than that of pink mudstone.(4)Use geo-slope software to analyze the slope stability of open-pit mine slopes in high and cold areas by limit equilibrium method.According to the parameters obtained by the direct shear test under the freeze-thaw cycle,the calculation and simulation of the slope under freeze-thaw conditions It is known that the slope of the open-pit mine in the seasonally frozen area is significantly affected by water and temperature factors.The number of freeze-thaw cycles is closely related to the ultimate bearing capacity of the mudstone.The research conclusion can provide a theoretical basis for the safety of slope mud and freeze-thaw damage of mudstone in Xinjiang.The paper has 92 pictures,17 tables,and 77 references.