Study On Simulation Test Of Rock Mass Shear Failure And Acoustic Emission Characteristics

In recent years,the stability of rock and soil has aroused widespread concern in the engineering community.The engineering conditions are complex and the scale of the project is large.The shape of the rock mass force itself,such as the size of the joint inclination and the undulation height of the joint surface,will have varying degrees of influence on the engineering properties of the rock mass itself.Therefore,in view of the existing problems in these engineering fields,this paper takes the study of rock mass failure characteristics as a foothold to analyze the shear failure characteristics.Through uniaxial compression and direct shear tests,the strength and deformation characteristics of rock masses are studied,and the shear tests of similar rock mass tests are conducted with a set of test ratios to study the shearing of joint planes by normal stress and undulation angle The research results of mechanical behavior and acoustic emission characteristics are as follows:According to the orthogonal test of 25 groups of similar materials,the basic physical dimensions were studied.Three factors were set as the control indicators: bone cement ratio,water paste ratio,and barite powder percentage content.The results showed that: 1.The density varies with the bone cement ratio and water paste ratio.The ratio increases with the increase of barite powder content.It first increases and then decreases with the increase of barite powder content.2.The bone-to-glue ratio has the greatest impact on the compressive strength.The compressive strength decreases with the increase of the bone-to-gel ratio and the water-to-paste ratio.The increase in the percentage of barite powder first increases and then decreases.3.The elastic modulus firstly increases and then decreases with the ratio of bone-to-glue,water-to-paste ratio,and the percentage of barite powder.4.The internal friction angle increases with the increase in the ratio of water-to-paste and bone-to-paste ratio,and increases with weight.The content of spar powder increases and decreases;5.The cohesive force decreases with the increase of the proportion of bone glue,and increases with the increase of barite powder content.Through a set of mixing ratios for shear and acoustic emission tests,three specimens of complete rock mass,perforated jointed rock mass and non-perforated jointed rock mass were produced.When the undulating angle of the through-joint rock mass is 30°,the failure form is wear failure.As the undulating angle increases,the failure mode is mainly shear failure;the same points of the three types of rock masses follow the normal stress Increases,the peak shear stress of the specimen also increases.Through analysis,it can be considered that the peak shear stress increases linearly with the normal stress;with the increase of the normal stress,the difference between the intact rock mass and the discontinuous jointed rock mass The peak tangential displacement has increased,the peak tangential displacement of the through-joint rock mass decreases with the increase of the normal stress;for the through-joint specimen,the tangential displacement decreases with the increase of the undulation angle,and the non-through-joint specimen The tangential displacement increases with the increase of normal stress.With the increase of the undulation angle of both types of rock masses,the peak shear stress will also increase.The main feature of acoustic emission technology is that it can track and monitor the dynamic changes of rock damage,and it is a new type of non-destructive monitoring equipment.Research on three types of rock masses found that under the same undulating angle,with the increase of normal stress,the ringing count and energy have a decreasing trend;under the same normal stress,as the undulating angle increases,Acoustic emission ringing and energy tend to increase gradually.Ringing count and energy count have the same trend with the whole process of shear failure,and acoustic emission can replace each other in theory between ringing count and energy.Therefore,the acoustic wave characteristics of acoustic emission can reflect shear failure.The characteristics of dynamic changes.