Research On Friction Test At The Bottom Of The Large Rockslide Sliding Zone

Landslide is one of the most important geological disasters in the world and has brought huge losses to human environment and production and life.For the landslide,the sliding is an important part of the landslide,and the determination of the strength of the sliding is the key foundation to study the stability of the landslide.The frictional strength of the sliding belt at the bottom of the large landslide has a great influence on the occurrence,migration and influence of the landslide.Therefore,it is of great practical significance to study the strength of the landslide.The authors carried out field investigation and got the samples from sliding zone.The shale of the jiwei mountain landslide,mudstone of the kualiangzi landslide,limestone of the daguangbao landslide.Then get the samples back to laboratory to do the experiment study.Do the friction test in the slide of mud with kualiangzi.Do the friction test between landslide sliding mud and sliding zone of rock mass with jiwei mountain,kualiangzi and daguangbao.Do the friction test in sliding zone rock mass sliding zone with jiwei mountain,kualiangzi and daguangbao as the research object,the sliding zone soil friction experiment was carried out respectively.Do the stress path test with kualiangzi.The experimental study on the friction strength of landslide is carried out.The main research contents and achievements in this paper can be summarized as follows:(1)Firstly,the landslide belt is surveyed and the slippery soil and the bottom slip belt are obtained.The material composition and physical and chemical properties are analyzed.The bottom slip belt is described,and the landslide The direction of movement of the body,different rock scratches were compared.(2)Respectively on the sliding zone in jiwei mountain for mud and rock mass,kualiaingzi landslide at the bottom of the sliding zone soil and the sliding zone,daguangbao sliding zone and broken rock mass uniform friction experiment was carried out.From friction strength,friction stress ratio,internal friction Angle of acoustic emission signal strength,comparing the aspects of friction strength of the sliding zone below the sliding zone between soil and sliding zone rock mass friction strength,friction between sliding zone rock mass friction strength of the highest.In a saturated state,the sliding friction strength of the friction strength under dry condition.The speed test study on the sliding zone,increased from 0.08 mm/min speed level 5 to 120 mm/min,the speed of sliding friction strength increased when speed increase,friction stress ratio increases.In the same test conditions,when rock lithology harder,the higher the strength of sliding friction.(3)The acoustic test of the friction test,non-destructive testing of the rock structure in the test process of the defect state.The acoustic emission is more sensitive to structural defects caused by external forces,and the unstable defects of the specimen itself do not produce acoustic emission signals.It can be concluded that the intensity of the acoustic emission signal in the saturated state is greater than that in the dry state,and the friction of the rock mass is more tight in the saturated state,and the collision is broken and the more severe signal is generated.The friction signal of the sliding zone is more dense than the friction signal of the sliding zone,and the particles on the surface of the sliding zone are fragmented in the friction process to produce a large number of acoustic emission signals.The surface part of the sliding zone rock mass is broken and the acoustic emission signal,As the displacement increases the crushing process tends to be gentle,the acoustic emission signal is reduced.In the high-speed friction process,the energy of the friction signal is larger than that of the low-speed friction process.The number of collision particles in the high-speed friction process increases and the degree of crushing increases,resulting in a stronger signal.The surface particles of the slow friction process are mainly oriented,The intensity of the acoustic emission signal is low.(4)The stress path test is carried out on the kualiangzi slippery soil.In the case of different slip angles,the normal stress is 200 kPa or 300 kPa,and the slip angle is 2 °,4 °,6 °,8 ° and 10 °.At the same time,the shear stress and normal stress are increased.Surface movement state.With the increase of sliding angle,the sliding speed increases with the inclination of the sliding surface.When the sliding angle is less than 6 °,the sliding velocity is finally reduced to 0,and the stability coefficient is less than 1.When the sliding angle is greater than 6 °,the sliding speed will increase significantly after a displacement,the stability coefficient is greater than 1 and rising,into the damaged state.It is shown that when the rainfall infiltration does not reach the slip surface,only the upper slippage is changed,which has important influence on the landslide movement.The stability of the landslide is also very sensitive to the inclination of the sliding surface.