泊松比对巷道稳定性影响的数值模拟试验研究

Numerical simulation study on influence of Poisson's ratio on roadway stability

泊松比是分析岩体性质的重要物理力学参数之一。为了分析泊松比对巷道稳定性的影响,从泊松比测定与计算方法着手,采用金尼克假说,以巷道侧压系数为研究对象,运用ANSYS软件,建立典型矿山巷道锚喷支护后的数值模型,通过设置沿拱角径向的安全系数监测点,建立巷道安全稳定范围与泊松比的对应关系。研究表明,随着泊松比μ值的增加,巷道拱角处不稳定区域逐渐减小,并向顶底板延伸,巷道两帮的塑性破坏区无明显变化;泊松比μ值为0.20时,塑性破坏区面积较大,为巷道断面面积的5.10倍;泊松比μ值(x)与安全系数≥1的区域距离拱角径向位置(y)的关系式为:y=61.518x2-54.509x+12.516。研究为泊松比对巷道稳定性影响提供了一定的理论参考依据。

The Poisson＇s ratio is one of the important physical and mechanical parameters to analyze the properties of rock mass. In order to analyze the influence of Poisson＇s ratio on roadway stability,starting from the determination and calculation methods of Poisson＇s ratio,a numerical model of typical mine roadway with bolt- shotcrete support was established by using ANSYS software through adopting the Dinnik＇s hypothesis and taking the side pressure coefficient of roadway as the research object. The corresponding relationship between the safety stability range and the Poisson＇s ratio of roadway was established by setting the monitoring points of safety coefficient along the radial direction of arch angle. The results showed that with the increase of Poisson＇s ratio μ value,the unstable zone at the arch angle of roadway reduces gradually and extends to the roof and floor,while the plastic failure zone on both sides of roadway have on obvious change. When the Poisson＇s ratio μ value is 0.20,the area of plastic failure zone is larger,which is 5. 10 times of the cross section area of roadway. The relationship between the Poisson＇s ratio μ value（ x） and the radial position of the zone with safety coefficient great than or equal to 1 away from the arch angle（ y） is y = 61. 518x2- 54. 509 x ＋ 12. 516. The research provides a theoretical reference and basis for the influence of Poisson＇s ratio on roadway stability.