Theoretical Anchor Hole Wall Shear Stress Of The Interface And Neural Network Research

Based on the analysis of key factors anchored on the failure to determine theinterface on the anchor hole wall shear stress as a key study. Anchoring according todifferent classification can be divided into many forms, determined in accordancewith anchorage length here, anchoring the form of axial force, with or without preloadclassified in three ways on the anchor role, combined with FLAC3D simulationresults for different types of analysis anchoring can be anchoring hole wall shearstress distribution on the interface is divided into three parts elastic zone, plastic zone,the slip area, and three after three face-like body were carried out a detailed analysis.Combined analysis of elastic-plastic mechanics to get the anchor hole wall shearstress at the interface elasticity and plasticity slip state expression, and the expressionand pull-out test results are qualitatively analyzed key factors, identified several thekey factors influencing the manner and degree of influence on the hole wall shearstress of the interface. The effect of hole diameter, lithology, anchorage length of theinterfacial shear stress, and try to use the neural network approach to the hole wallinterfacial shear stress distribution to predict the effect achieved better forecast. Themain results are as follows:(1)Theoretical analysis method to establish a mechanical model of the cell wallinterface shear stress, and proposed a definition of anchor, anchor of the Communityelastic modulus formula, can be combined to facilitate a variety of different intensitiesof anchor and anchor agent modulus of elasticity. And on this basis, according to thecorrected elastic model, analyze, and rock lithology, hole diameter, the impactstrength of the anchoring agent interface shear stress distribution on the anchor, andthe impact on the bolt axial force.(2)Use bolt anchoring effect is more ideal in a relatively soft rock. A relativelylarge borehole better results. With the increase of the elastic modulus of Anchorage,Anchorage bond stress distribution at the interface is more extensive, stressconcentration smaller and more uniform. Therefore, the application of high elasticmodulus better anchoring agent effect.(3)Anchorage length interfacial shear stress on the cell walls have a greater effect:With the increase in the anchorage length, the elastic limit and yield shear stress valueof the interface are increased correspondingly, and the residual shear stress isincreased. Residual shear stress is significantly greater than the hole wall roughness smooth bore wall. With the improvement of the strength of the anchoring agent,anchor-anchor agent interface shear stress elastic limit and yield values are increasedaccordingly.(4)Construct appropriate neural network structure based on neural networkmatlab toolkit. It can be seen on the basis of the analysis of the linear neural networkmodel has good predictive ability. Able to draw reasonable prediction accuracy can bepredicted well bore wall shear stress distribution on the interface.