【作者】 郑西贵；

【导师】 张农；

【作者基本信息】 中国矿业大学 ， 采矿工程， 2013， 博士

【摘要】 针对煤矿巷道预应力锚固技术，采用理论分析、实验室实验、数值计算、现场实测等综合研究手段，系统研究了初始托锚力与预紧力矩的转换关系，提出了临界预紧力矩的概念；分析了托锚力在掘采过程中的波动演化特征和影响因素，揭示了托锚力在围岩变形破坏过程中的演化机理；提出了协同承载原理，创新了稳定托锚力的技术方法，并开展了工程实践验证研究，主要结论如下：（1）研究了锚杆托锚力与预紧力矩的转换关系，托锚力沿轴向方向的应力分布情况和影响因素。通过测试常规系列锚杆在自制实验台及井下水平层状围岩、煤壁和喷砼表面等3种工程界面预紧力矩和托锚力的转换关系，发现了扭矩系数趋于定值的现象，提出了临界预紧力矩的概念，即托锚力与预紧力矩线性增长且扭矩系数达到稳定时的扭矩，特定条件下测得的数值为200N·m左右。（2）分析了层状岩体的锚固段粘结应力分布特征，修正了剪切滞力学模型，解释了层状岩体逐层脱粘累次破坏的现象，提出了渐次脱锚判据，揭示了托锚力振荡波动的机理。（3）实测了7条深井巷道顶板64组锚杆和47组锚索的托锚力，得出了托锚力波动的基本规律。总结了影响托锚力波动的关键因素，包括层理数目、初始预紧力、采动应力和护表构件刚度等；归纳了掘采全过程工作托锚力演化的8种类型，其中利于工作托锚力稳定和围岩控制的类型有稳定型、跃升趋稳型、单一渐增型、单一缓降型和缓降趋稳型；不利于围岩稳定和安全的有瞬降失效型、锯齿振荡型和台阶下降等类型。（4）分析了托锚力损耗与围岩破坏的关系，总结了托锚力完全损耗、部分损耗、无损耗的原因，及其对应的巷道支护失效、低效和大变形规律，采用FLAC3D数值软件计算分析了锚杆预紧力的合理取值，提出了利用高预紧力锚索和高刚度护表构件消除锚杆尾端拉应力的协同承载技术体系，分析了锚固剂粘结性能、锚固长度等对此体系的影响。（5）基于协同承载原理，创新研制了均匀承载的碟形锚索托盘、带筋的高强T形钢带、带托盘的高强钢带和锚杆柔性锁紧结构等系列护表构件，形成了托锚力长时稳定的控制技术。研究成果在淮南矿业集团潘一矿东区1252(1)首采工作面轨道顺槽沿空留巷、丁集矿1252(1)工作面轨道顺槽小煤柱沿空掘巷和大屯矿区孔庄矿-1015水平混合井筒马头门的加固等地点进行了成功实践，取得了较好的社会和经济效益。论文共有图93幅，表20个，参考文献191篇。更多还原

【Abstract】 Aimed at the control technology of prestress anchoring in mine entry, there takeda systematic research on the transformational mechanism of initial anchoring forceand pre-tightening torque by the comprehensive research of experiment, fieldobservation, mechanical analysis model and numerical calculation etc. there alsoanalyzed the fluctuate evolution law and factors for the anchoring force during theperiod of extraction, and put forward the theory of critical pretightening torque.What’s more, this dissertation revealed the evaluation law of anchoring force duringthe surrounding rock’s destruction and the theory of synergistic bearing, theseachievement innovate the technical method for stabilizing anchoring force,engineering practice also been taken into this research and the main conclusions are asfollows.(1) Analyzed the transformational relationship between bolt’s lift anchoring forceand pre-tightening torque, the stress distribution and factors of lift anchoring force inthe bolt’s axial direction also been taken into consideration. Get the conclusion thattorque coefficient tends to be a constant value and the concept of pre-tighteningtorque was put forward, which can be demonstrated by testing the conversion betweendifferent lift anchoring force and pre-tightening torque, the experiment based on theintegrated testing bench with prestressed anchor system and three kinds ofengineering interfaces such as layered rock surface, rough coal face and smoothinterface after shotcrete.(2) Based on analysis to bond stress and mechanical transmission in theanchoring segment of strata rock mass, this dissertation amended shearing hystereticmodel, and explained the phenomenon of debonding seriatim and iterated destroy instrata rock mass, then proposed the criterion for taking off anchoring seriatim andrevealed the mechanism of fluctuant vibration in lift anchoring force.(3) Measured the roof’s lift anchoring force of bolts (62groups) and cables (47groups) in7deep-mine roadways, and summarized the basic laws of the fluctuation inlift anchoring force, concluded that the fluctuation in lift anchoring force can beinfluenced by several factors such as strata numbers, initial pretightening force,mining-induced stress and stiffness of the surface supporting component etc.. Sumedthe working lift anchoring force up in eight types during the overall period ofexcavation and mining, there are stable type, zooming first and then tend to be stable,sole increasing types, sole slow descent type, slow falling first and then tend to be stable, zigzag vibration and step down type etc., among all of these types, the lastthree types aren’t beneficial to the stable and safety of surrounding rock while theothers are.(4) By making a survey on the bolt supporting roadway in several mines, thisdissertation analyzed the relationship between the loss of lift anchoring force and thedamage of surrounding rock, summed up the reason of complete loss in lift anchoringforce, partial loss and no loss, which are corresponding to supporting failure,inefficient and large deformation of the roadway respectively. Combined withnumerical calculation software FLAC3D, reasonable value of pretightening force wasanalyzed too. Then presented the synergistic bearing system that can eliminate thetensile stress in bolt’s tail end by using high pretightening cable and surfacesupporting component with high stiffness. Bonding property and anchoring length ofanchoring agent also been taken into consideration.(5) Based on the theory of synergistic bearing, there formed the technology ofcontrolling bolt’s anchorage force with secular stability by creating products withhomogeneous bearing capacity such as dishing cable tray, ribbed high-strength&bending-resistant steel belt shaped like T, composite steel belt with high strength andflexible bolt’s locking structure.Better social and economic benefits can be acquired by putting aboveconclusions into practice such as tail entry’s gob-side entry retaining of first miningface1252(1) in Pan yi-dong mine, tail entry’s gob-side entry driving with coal pillarretaining of face1252(1) in Dingji mine, reinforcement for ingate of mixing shaftunder level-1050in Kongzhuang mine, the first two mines belonged to HuainanMining Group while the last one to Datun mining area.There are93figures,20tables and191references in this dissertation.更多还原