Research On Mechanic Properties Of Anchoring Materials Based On Thermodynamic Coupling Effect

Along with the increase of mine depth, the high temperature and high stress condition of deep surrouding rock become more and more complex, so as the mechanical properties of supporting materials. And the nonlinear deformation phenomenon of roadway bolting system is ubiquitous.The destruction phenomenon of roadway supporting system occurs frequently which leads to increasing dasaster. Severe challenges has beening posed to construcions. Because of this, the paper povides strong basis to support system of resin anchor, by grouping resin anchor, analysis of resin mechanism, reseaching damage patterns and failture mechanism.Aiming at high temperature and high stress in complex geological conditions, the paper discussed the analysisi method of thermal coupling problem by combining it with practical engineering. On the basis of the thermal coupling effect analysis theory, it also studied the change rule on mechanical properties of anchorage materials with the temperature under the thermal coupling. Laboratory model tests under different constant temperature environment, are adopted to simulate the mechanical behavior of anchorage materials in actual resin bolt support system, with the purpose to find out the damage factors and depormation failure mechanism of the system. Experimental results show that: in the constant temperature40℃environment, A set of drawing force peak average value was25KN and shear stress was35.4MPa. In the constant temperature60℃environment, group B peak average value was24KN, and shear stress was34MPa. In the constant temperature80℃environment, group C peak average value was23KN, and shear stress was33MPa. And the last group D peak average value was19KN, and shear stress was27.3MPa. Under the thermal coupling effect, the bond strength of resin anchoring materials decreases with the rise of temperature, in the same time, the reinforcement of drawing force increases exponentially with the temperature rise. The attenuation rate of drawing force was4%under low temperature which was17.4%in high temperature conditon. The attenuation rate of shear stress was3.45%and17.3in each situration as above. Hihger temperature leads to faster attenuation of drawing force.The last part was numerical simulation analysis. Anchoring material mainly follow the linear elastic-plastic constitutive relation. Loading temperature and tensile force, the mechanical properties of anchorage was analysised and studied under the effect of thermal coupling. The calculation results show that: under the effect of thermal coupling, the yield strength of resin anchoring materials decrese exponentially with temperature rise. In the environment of constant temperature40℃, the shear stress reached38MPa when anchoring material break, which reached30MPa when the temperature was60℃. Difference between laboratory model test results yield strength was6.8%. Anchoring material produces linear expansion deformation with temperature increase which lead to higher stress of anchorage materials. Steer constraint outside the simulative drilling hole made the friction force in the anchorage material increase, and the increase of Angle of internal friction eventually cause change of damage types. Structure perpormance parameters of anchorage materials change under the action of thermal coupling, intensity of bonding surface drops after microcracks emerged, anchoring material change directly into bond failure from original shear failure. Therefore, in roadway of resin bolt support in deep well, that strenthening ventilation and cooling as actively research and development of high temperature resistant resin anchoring material is the important guarantee of roadway support system stability and security.