基于PFC的玻璃钢锚杆应力分布规律及影响因素研究

发布时间：2018-08-07 17:57

【摘要】：本文通过了数值模拟的方法对玻璃钢锚杆在载荷作用下界面上的剪应力和轴力分布规律进行了研究,并且通过改变锚杆和锚固剂的参数来探究锚杆应力分布规律影响因素,最终达到优化设计的目的。利用了 PFC细观颗粒流软件对玻璃钢锚杆在拉拔过程中的应力分布特征进行研究。并将所得出的结论应用于保德煤矿掘进工作面的支护,从而验证了数值模拟方法对锚杆研究的准确性。锚杆的界面应力传递规律和分布情况对巷道围岩锚固机理的研究非常重要。数值模拟结果表明:玻璃钢锚杆在拉拔过程中,剪应力的分布由锚杆的孔口开始呈现先增后减的分布形式,最大值的位置距离孔口较近。锚杆的轴力呈现出递减的变化趋势。通过模拟不同因素下锚杆应力分布规律我们可以看出:锚杆直径、锚固剂弹性模量、锚固长度和锚杆的弹性模量对锚杆应力分布有影响。锚固剂的弹性模量越大,锚杆的剪应力越集中,轴力的变化幅度越大。随着锚杆弹性模量的增加,轴力逐渐增加,在锚杆两端出现轴力变化幅度较小,在锚杆中部轴力变化幅度较大。随着锚杆直径的增加,锚杆受到的轴力减小,在孔口位置轴力的减小幅度最大,随着锚固深度的增加,轴力的减小幅度放缓。锚杆轴力的变化幅度也随着锚杆直径的增加逐渐放缓。随着锚杆锚固长度的增加,锚杆所受到的剪应力和轴力并不是线性变化,而是在一定范围内随着锚固长度的增加,剪应力和轴力逐渐降低,当锚固长度达到一定大小时,剪应力又会继续增大,所以存在着最佳锚固长度。
[Abstract]:In this paper, the distribution of shear stress and axial force on the interface of FRP anchor under load is studied by numerical simulation, and the influencing factors of stress distribution of anchor are discussed by changing the parameters of anchor rod and anchoring agent. Finally, the purpose of optimal design is achieved. The stress distribution characteristics of FRP anchor during drawing are studied by PFC software. The conclusion is applied to the support of the driving face in Baode Coal Mine, which verifies the accuracy of the numerical simulation method for the study of the bolt. The law of interfacial stress transfer and distribution of bolt is very important to study the anchoring mechanism of roadway surrounding rock. The numerical simulation results show that the distribution of shear stress increases first and then decreases from the orifice of the bolt during drawing, and the maximum value is close to the orifice. The axial force of the bolt is decreasing. By simulating the stress distribution of anchor rod under different factors, we can see that the diameter of anchor rod, the elastic modulus of anchoring agent, the length of anchor and the elastic modulus of anchor rod have influence on the stress distribution of anchor rod. The greater the elastic modulus of the anchoring agent is, the more concentrated the shear stress is, and the greater the variation of axial force is. With the increase of elastic modulus of anchor rod, the axial force increases gradually, the variation range of axial force at both ends of anchor is smaller, and in the middle of anchor is larger. With the increase of anchor diameter, the axial force of the bolt decreases, and the decrease of axial force at the orifice is the largest. With the increase of anchoring depth, the decrease of axial force slows down. The variation of the axial force of the bolt also slowed down with the increase of the diameter of the bolt. With the increase of anchoring length, the shear stress and axial force are not linearly changed, but decrease gradually with the increase of anchor length, when the anchoring length reaches a certain size, the shear stress and axial force decrease gradually with the increase of anchoring length. The shear stress will continue to increase, so there is an optimal Anchorage length.
【学位授予单位】：安徽理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TD353.6

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