【作者】 薛道成；

【导师】 缪协兴；

【作者基本信息】 中国矿业大学 ， 采矿工程， 2013， 博士

【摘要】 锚杆支护具有成本低和施工简便等优点，是煤矿巷道的主要支护形式。锚杆支护质量和性能的无损检测一直是国内外科技界探索的重点研究方向之一。本文基于结构动力学原理，采用理论分析、试验研究和现场检测等手段，研究了锚杆锚固结构系统的纵向和横向动力学特征，提出了锚杆锚固质量的动力无损检测方法，研发了相关的检测系统，并在西山矿区进行了验证和应用。本文的主要研究工作和成果如下：(1)基于动力学原理建立了锚杆锚固结构系统的纵向振动力学模型，研究了弹性波在锚固界面及底端处反射与扩散规律等。研究结果表明纵向的弹性波在锚固端面有一反相的反射波，在锚杆末端有一同相反射波。由此提出了锚杆自由段长度和锚固长度的无损检测方法。(2)建立了锚杆锚固结构系统的横向振动力学模型，给出了锚杆轴向受力对系统动力特性的影响规律。结果表明锚固系统横向振动的固有频率随锚杆轴向受力的增加而增加，两者之间可以很好地用对数关系描述。由此提出了锚杆轴向受力的实时无损检测方法。(3)采用模块化的设计方法开发了锚杆无损检测系统。该系统包括激振模块、信号采集模块、数据处理模块和智能识别模块。并基于系统的室内和现场试验研究，确定了检测系统的构成及参数，如激震方式，采样频率等。(4)自主设计了锚杆无损检测实验系统和模拟现场条件的试验巷道，对锚杆支护质量无损检测系统进行了验证试验。试验结果表明：所开发的锚杆无损检测技术能较好的检测出锚杆的锚固段长度和全长，其误差在2%以内；锚杆锚固系统的横向振动频率与锚杆的轴向受力是紧密相关的，且该关系受围岩性质的影响。基于试验结果，提出了锚杆特征长度自动识别算法以及不同围岩岩性条件下锚杆轴力的检测程序。(5)选择西山矿区两个典型矿井进行了工程应用，对两矿中具有不同地质条件和支护参数的多条巷道中的锚杆进行了长期的检测和监测。结果表明，本文开发的锚杆无损检测技术具有实用性和可靠性，锚杆长度检测准确率在95%以上；轴力检测实施快速，结果直观。根据锚杆检测数据，针对西山矿区地质条件的特殊性，编制了可给出锚杆锚固质量的统计规律及分布状态的评价系统软件，并基于该软件评价了所检测巷道的锚杆支护质量，提出了相关的建议。本文研究成果不仅可为锚杆无损检测技术提供基础的理论支持，亦可为巷道锚杆支护质量检测和评价提供有效的技术手段。论文有图106幅，表23个，参考文献126篇。更多还原

【Abstract】 Rock Bolting has the advantages of low cost and simple construction, and has beenthe main form of support for coal mine roadways. The non-destructive detection of thequality and performance of rock bolt has been one of the key research directions athome and abroad. Based on the principles of structural dynamics, the longitudinal andlateral dynamics characteristics of the rock bolt structural system has been studied herevia theoretical analysis, experimental research and field testing. Then, thenon-destructive detection method of rock bolt quality was proposed, and the detectionsystem was designed and applied in Xishan mining area. The main research work andachievements are as follows.(1) The longitudinal vibration mechanical model of elastic waves in rock boltstructural system is established, based on the dynamic theory. According to themechanical model, the reflection and diffusion character of elastic wave at theanchoring interface and bottom of rock bolt is studied. The results show that thelongitudinal elastic wave has a reflected wave with an inverting phase at the anchoringinterface, and a reflected wave with a same phase at the bottom of rock bolt. Then, thenon-destructive detection method of free length and anchorage length of rock bolt isproposed.(2) The lateral vibration mechanical model of the anchoring system is established,and the influence of the rock bolt axial force on the dynamic characteristics of theanchoring system is analyzed. The results show that the horizontal natural frequenciesof the anchoring system increase with the increase of the rock bolt axial force. Themechanical response of the interface between the pallet and surrounding rockdetermined the relation between the horizontal natural frequencies and axial force.Then, the non-destructive detection method of the axial force of rock bolt is proposed.(3) A non-destructive detection system is developed through modular designmethod. The system includes exciting module, signal acquisition module, dataprocessing module and the smart identity module. Based on laboratory and field tests,the components and parameters of the detection system are determined, such as shockmethod and the sampling frequency, etc.(4) In order to test and verify the function of the detection system, anon-destructive detection experimental system and simulated roadway are designed in the laboratory. The experimental results show that the detection system proposed heremay effectively detect the free length and anchorage length of rock bolt, and the erroris within2%. The lateral vibration frequency of the anchoring system is closely relatedto the axial force of rock bolt, and the relation is influenced by the character of thesurrounding rock. Based on the experimental results, the automatic recognition forcharacteristic length of rock bolt is proposed, and the detection method of the axialforce under different conditions of surrounding rock is put forward.(5) The engineering application is carried out in two typical coal mines in Xishanmining area, which are Xiqu coal mine and Duerping coal mine. The rock bolts inseveral roadways from the previous coal mines are detected and monitored. The resultsshow that the detection system developed here is practical and reliable. The rock boltlength detection accuracy rate is more than95%and the axial force detection may givefast and intuitive results. Based on the field testing results, an evaluation system for theanchoring quality is presented according to the special geological conditions in Xishanmining area. The evaluation system may give the statistical regularities and distributionof anchoring condition. At last, some assessment and suggestions are proposed for theanchoring quality in the detected roadways.The results of this study may not only provide basic theoretical support for rockbolt non-destructive detection, but also provide technical methods for evaluation on therock bolt support.This thesis has106figures,23tables and126regferences.更多还原