基于FLAC^(3D)的中空注浆锚索数值分析  

Numerical Analysis on Hollow Grouting Anchor Cable Based on FLAC^(3D)

作　　者：刘娜[1,2] 黄中峰 郑西贵[3] 

机构地区：[1]中煤科工集团重庆研究院有限公司,重庆400037 [2]瓦斯灾害监控与应急技术国家重点实验室,重庆400037 [3]中国矿业大学矿业工程学院,江苏徐州221116

出　　处：《煤矿安全》2016年第6期194-197,201,共5页Safety in Coal Mines

基　　金：中煤科工集团重庆研究院有限公司青年创新基金资助项目(2014QNJJ22);国家自然科学基金青年科学基金项目(51104152)

摘　　要：针对中空注浆锚索出现的受力问题,利用FLAC^(3D)内置的cable结构单元对中空注浆锚索进行模拟拉拔实验,分析中空注浆锚索在全长锚固时锚索在不同拉拔载荷下围岩和锚索的应力位移演化规律以及锚索轴力演化特征。模拟结果表明:在相同拉拔载荷下,中空注浆锚索周围0~0.5 m范围内的围岩,越靠近中空注浆锚索的围岩位移变化量越大;在不同载荷同一位置围岩的位移随着拉力的增加而逐渐增大,围岩位移沿着索体径向方向上总体呈负指数下降,随着拉力逐渐增加,在锚索与锚固剂的连接面处岩体应力由拉应力逐渐变为压应力。当拉拔载荷在400~440 kN时,锚索位移量突然增加,锚索逐渐发生破坏,破坏之前,最大位移量达到250 mm左右,瞬间被拉断后,锚索位移量达到400 mm左右。在不同拉拔载荷下,锚索受力由锚索底部逐渐传递到锚固段,剪切滑移破坏逐渐上升,最终导致锚索发生破断。通过模拟和现场实践表明应用中空注浆锚索支护巷道具有一定实用性。In view of the problem of load distribution along hollow grouting anchor cable,we carry out tensile experiment on this instrument with the assistance of incorporated cable structural unit in FLAC（3D）,and we also analyzed the stress-displacement laws of full-length cable and surrounding rock mass and axial evolution laws of cable under different tensile load. The result shows that rock mass ranges from 0 m to 0. 5 m around the cable shows larger displacement as the range shrinks. Displacement of rock mass in the same place increases as the tensile load rises; generally,displacement of rock mass shows negative exponent decrease along radical direction of cable. Tensile stress along the cable-grouting interface will gradually turn into pressure stress as the tensile increases. Displacement of cable shows dramatic increase as the tensile load reaches 400 kN to 440 kN,hence,breakage can occur along the cable. The maximum displacement before breakage can reach to 250 mm or so; this value can turn into 400 mm after the immediate fracture of cable. Load of cable transfers from loading end to grouting end under different tensile load,and the shear sliding failure will gradually increases,it thus causes the fracture of cable. It is feasible to conduct this procedure of grouting cable based on FLAC（3D） and the results also confirm to field trial.

关 键 词：中空注浆锚索 拉拔载荷 FLAC3D 数值模拟 围岩位移 

分 类 号：TD353[矿业工程—矿井建设]