微膨胀锚固剂膨胀应力分析及性能试验研究

Analysis of Expansion Stress and Experiment Research on Performance of Micro-expansion Anchoring Agent

基于弹性力学厚壁筒理论,建立了膨胀应力分析模型,分析了膨胀压力与拉伸应力的转换机理,推导得出无限大区域膨胀拉伸应力计算公式,指出无限大区域内岩体径向压应力σρ和环向拉伸应力σφ大小相等,均与岩体所处位置至钻孔中心的距离ρ成反比,与钻孔半径r和孔壁内压力P内成正比,在此基础上研究了岩体产生拉伸破坏的条件,结合岩石极限抗拉强度和微膨胀树脂锚固剂的最大膨胀拉伸应力,给出了UEA膨胀材料的配比范围,并通过单轴抗压试验证明了UEA膨胀剂对树脂锚固剂力学性能基本没有影响,可以满足使用要求。

Expansion stress analysis mode has been established based on the thick-walled tube theory of elasticity,the calculation formula of infinite media expansion tension stress has been deducted after the analysis of conversion mechanism between expansion stress and tension stress.The formula showed that rock mass radial compressive stress（бρ）and circumferential tension stress（бφ）were equal within infinite media,both of them were inverse proportional to the distance（ρ）of rock location between drilling center,and directly proportional to drilling radius（r）and the pressure inside hole wall（p）.The paper has studied the condition of rock mass producing tensile failure,given the ratio range of UEA expansion material combined with rock ultimate tensile strength and the largest expansion tensile stress of micro-expansion resin anchoring agent,and proved that UEA expansion agent had little influence on mechanical properties of resin anchoring cartridge by uniaxial compressive test,which can meet the requirements.