小孔径预应力锚索内锚力增强技术研究
Study on internal anchoring force enhanced technology of small diameter hole pre-stressed anchoring cable
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摘要: 为解决目前深井高应力及复杂环境下巷道存在的小孔径预应力锚索内锚强度低、锚固可靠性差的问题,采用现场调研、实验室仿真试验方法,分析总结了常规预应力锚索可能的失效原因,指出锚索索体光滑是导致锚索内锚可靠性较低的重要原因之一,基于上述研究提出了一种内锚力增强技术即叶片式锚索锚固结构。实验室仿真试验及现场工程应用结果表明:叶片式锚索能够有效避免钢绞线穿过锚固剂而发生的假性锚固;能够将树脂锚固剂聚酯薄膜包装袋充分搅碎,并将固化剂与胶泥充分混合均匀,对提高锚索内锚强度、锚固可靠性及控制高应力、深部复杂巷道围岩变形效果显著。Abstract: In order to solve a low internal anchoring strength of the small diameter hole pre-stressed anchor cable and poor anchoring reliability problems existed i n the mine roadway under the conditions of the present high stress in the deep mine and the complicated environment, a site investigation and lab simulation test meth od was applied to analyze and summarized the possible failure causes of the conventional pre-stressed anchoring cable. The paper pointed out that a smooth body of t he anchoring cable was one of the important causes to cause a low reliability of the anchoring cable. Based on the above study, a internal anchoring force enhanced te chnology, namely the anchoring structure of the vane type anchoring cable was provided. The lab simulation test and the site engineering application results showed th at the vane type anchoring cable could effectively avoid the pseudo anchoring occurred when the steel strand passed through anchoring cartridge, could fully crush the polyester film packing bag of the resin cartridge, could fully and evenly mix the curing agent and the clay and could improve the internal anchoring strength of the ancho ring cable and the anchoring relibility as well as could control the high stress and the surrounding rock deformation of the complicated roadway with an obvious effect.