Experimental Study On Acoustic Emission Characteristics Of (Rock-like) Materials With Different Particle Size

In order to study the relationship between the mineral particles size of AE quiet period;Through the preliminary study on the particle size and acoustic emission characteristics of granite,quartz sand with different particle size is used.The results show that the mechanical properties and acoustic emission characteristics of the simulated materials in different particle compositions are discussed.The influence of different particle size of the rock form on the emission characteristics is discussed.In this paper,the indoor test is used as the research method,(0.1-0.2mm,0.63-1mm)and0.5:1(0.1-0.2mm: 0.63-1mm),1: 1,the concentration of sand was1: 4,the concentration was 70%,the curing period was 28 days(0.1-0.2mm,0.63-1mm)1: 0.5high-purity quartz sand simulation material and light gray coarse-grained granite rock material.The single-axis acoustic emission test was carried out.The main contents of this paper are as follows:(1)Of the quartz sand simulation materials and granite rock materials for uniaxial compression test.(2)The effect of particle composition on the acoustic emission characteristics was investigated.(3)from the perspective of particles with rock-like simulation materials to explore the rock material in the acoustic emission "relatively calm phenomenon" reasons.The conclusions are as follows:(1)The deformation characteristics of rock specimens with different particle sizes and different proportions are similar to those of rock materials,and can be roughly divided into: initial compaction,elastic deformation,plastic deformation,crack propagation.The size of the particles is different,the ductility of the specimen is different,and the ductility of the coarse particles is obvious.(2)The composition of different particles,affecting the uniaxial compressive strength of the material;fine particles of compressive strength is larger than the coarse particles,from 0.5: 1 to 1: 1 to 1: 0.5 with the proportion of fine particles increased And the uniaxial compressive strength of the rock specimen is increasing.(3)With the simulation material to verify the rock material in the composition and particle size of the same circumstances,rock materials and rock-like materials have occurred in some acoustic emission "relatively quiet phenomenon",while some are not.That is,the appearance of the sound emission quiet period and the composition of the particle form of the relationship between the rulesare is not obvious.(4)The peak frequency distribution range of the simulated material specimen with different particle size composition is mainly distributed in [10-120] KHz,the peak frequency distribution is different in each stage,and the particle size is 0.63-1mm.There are more low-frequency,the band gradually widened.(5)Particle size of the composition of different forms affect the characteristics of acoustic emission.In the quartz sand acoustic emission test of 0.1-0.2mm,0.63-1mm and 0.5: 1(0.1-0.2mm: 0.63-1mm),1: 1,1: 0.5,only 1: 0.5 test group was observed of the acoustic emission "relatively quiet phenomenon".(6)It can be seen from the(50)N /(50)E-value curve that the internal cracks in the specimen with different particle composition are different and the acoustic emission signal is different.The(50)N /(50)E-value curve of the coarse-grained specimen is mostly "stepped" Destruction in the late will produce a large number of low-energy test pieces.