温度对树脂锚杆锚固性能影响研究

为了分析在靠近自燃发火区的巷道进行锚杆支护时,树脂锚杆锚固力降低的现象,采用实验室试验和数值模拟相结合的方法进行了温度对树脂锚杆锚固性能的影响研究。不同温度下树脂锚杆拉拔试验结果表明:温度对树脂锚杆锚固性能影响比较大,温度为25℃时树脂锚杆锚固力最大,随着模拟钻孔温度的升高,树脂锚杆锚固力呈现明显递减规律;运用FLAC3D有限差分程序对单根锚杆支护小范围锚固系统的数值模拟结果表明:岩体应力场与温度场之间存在一定程度上的耦合作用,在相同外载荷作用下,热源温度不同,岩体应力分布状态也不同。在上述研究基础上,指出温度变化对岩体物理力学性质以及树脂锚固剂固化反应过程都会产生一定的影响,并提出了不同温度环境下保证锚杆支护效果的技术途径。

Study on Influence of Temperature on Anchorage Performance of Resin Anchored Bolt

To analyze the phenomenon that anchoring force of resin anchored bolt often decreased where rock bolting was carried out in the roadway near spontaneous combustion region,we studied the influence of temperature on anchoring performance of resin anchored bolts in this paper,by using the comprehensive research of laboratory test and numerical simulation.The results of pull-out tests of resin anchored bolts under different temperatures show that temperatures have great influence on anchorage performance of resin anchored bolt.The anchoring force is the largest when the temperature is 25℃,and the anchoring force descends obviously with the borehole temperature increases.Additionally,FLAC3D was adopted to simulate and analyze the anchorage system of single bolt support small-scale,and the results show that the coupled multi-physics processes exist to a certain extent between the stress field and temperature field of rock mass.The stress distribution states of rock mass are different under the same external load when the temperatures of heat source are different.On the basis,we find that the temperature variations have a certain effect on physical and mechanical properties of rock mass and curing reaction process of resin capsules,and put forward the technological approaches to ensure supporting effect under different temperatures.