Research On Bearing Plate Carrying Performance And Deformation Mechanical Behavior Based On Digital Speckle Correlation Method

Bolt support technology is widely used as an effective means of roadway surrounding rock control.The working load of the bolt is an important indicator of its working state.The bearing plate is the main component of the support system.The bolt support can be indirectly evaluated through the characteristics of the three-dimensional displacement field.Effectiveness,mastering its bearing characteristics and deformation characteristics have important significance for the stability of bolt support system.In this paper,a combination of theoretical analysis,numerical calculation and experiment is used to carry out the research on the bearing characteristics and mechanical behavior of the bolt bearing plate.Through the theoretical analysis,the deformation calculation formulas of each part of the bearing plate are derived.The ANSYS numerical simulation software is used to calculate the deformation values under different loads.Finally,the digital speckle correlation method is used to study the three-dimensional deformation mechanical behavior of the bearing plate.The following main conclusions are drawn:(1)Obtain the deformation calculation formula of the bottom of the bearing plate and the arch.Through the bending differential equation,the deflection function is constructed and the coefficient is determined by the energy method,and the deflection equation is expressed.The compression displacement of the arch is derived by the cross-section method and the micro-element,and the bending displacement caused by the load is superimposed,and the expression of the total compression and bending displacement is obtained.(2)Establish a three-dimensional model of the bearing plate and perform finite element analysis to obtain the bearing plate displacement distribution law.The maximum displacement vector increases linearly with the load.The maximum displacement vector appears at the four corners of the bearing plate,and the displacement value of the arch is the largest at the orifice.The bearing plate is mainly dominated by the four corners and the arch deformation.(3)Obtain the bearing plate stress distribution law,the equivalent stress value at the bearing plate orifice is the largest,and obvious stress concentration phenomenon appears,indicating that the rupture is most likely to occur.The stress concentration in the four corners,the midpoints of the four sides and the lower part of the arch is not obvious.(4)Obtain the bearing plate load-bearing performance law.The load-bearing capacity remains unchanged at the initial stage,then grows rapidly,then slowly increases to reach the peak load,and finally gradually decreases.The 160 mm bearing plate load-bearing performance is more superior.(5)Obtain the bearing plate deformation mechanical behavior characteristic law,divide the deformation into four stages according to the three-dimensional displacement field,the overall coordinate deformation stage,the bottom flattening stage,the four-corner uplift stage and the arch compression stage.There are 45 figures,2 tables,and 73 references in the paper.