| Bolt or cable supporting technology which is active supporting method to control thesurrounding rock stability has been widely applied in underground coal mining in China.Based on the complexity of surrounding rock, principles of bolt supporting have not yetcommon and completely understood, the bolt supporting need more study on the anchoragemechanism, interactive relationship with the surrounding rock, stress distribution along theembedded direction, bolt bearing characteristic and etc..This study took epoxy boned bolt system and bolt supported in coal mine roadway asresearch back ground, applied theoretical analysis, numerical simulation, field measurement,laboratory test and engineering practice to explore the mechanical behavior of epoxybonded bolt system and bolt bearing characteristic. The following findings were made:(1) Four main failure types of epoxy bolt supporting were analyzed and summaried,and imperfectly epoxy bonded failure and long-term creep failure of epoxy bonded boltsystem that belong to adhensive failure type were emphatically analyzed. A theoreticalmodel of epoxy bonded bolt system with an imperfect bonding adhesive layer was proposed,based on the this model, the formulas of axial stress in the blot and the shear stress at thebolt-epoxy interface along the embedded direction have been obtained and shown as apiecewise function. Simultaneously, an analytical model of epoxy bonded bolt systemconsidering the visco-elastic effect of the adhesive layer was developed, based on theproposed model, the time dependent formulas of tensile stress and shear stress at the boltand epoxy interface along the anchor's direction have been obtained. The closed formequation of the long-term load end displacement was derived, additionally, the timedependent of initial debonding load Pini.(2) Mechanical parameters of the surrounding rock, bolt, etc. were obtained throughlaboratory mechanical tests. Two suggested models were compared with the FEMsimulation in ABAQUS, then the distribution of bolt stress along the longitude direction ofbolt in both models were studied, and the evolution process of stress and displacement inbolt system were also presented. Subsequently, parametric study of the constituentparameters of the epoxy bonded bolt system, such as bolt diameter, epoxy layer thickness,etc. were conducted to demonstrate their effects on the the epoxy bonded bolt system.(3) Bolt performance comprehensive experiment bar for pre-stress bolt system andunderground bolt pull-out tests were used to study the distribution and bearing behavior ofepoxy bonded bolt system with different pre-stress, the relationship between pre-stress and displacement of bolt endpoint was alos carried out. The research results were preliminaryindicated that the bearing stress in bolt under its working condition was complicated andchangeable, and bearing stress concentrated around bolt neutral point.(4) Based on analysis of shortage of present roadway surrounding rock monitoringmethods and excellence of FBG sensing technology, a dynamic real-time monitoringsystem for roadway surrounding rock in coal mine was proposed and successly used tomonitor the distribution and evolution of stress in bolt in roadway in coal mine.(5) Finally, several principles to ensure bolt supporting effect were proposed based onthe above results and successfully appied in track transportation gateways of1115(3)working face of Guqiao coalmine and1115(3) working face of Zhuji coalmine, Huainanmining group. Simultaneously, track transportation gateway in1111(1) working face ofZhuji coalmine in Huainan mining group was took as engineering background, the real-timeon-line monitoring system for roadway surrounding rock activity in coal mine wassuccessfully applied to monitor the ground pressure during its gob-side entry retaining.
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