岩石压裂声发射源定位方法的数值模拟研究
发布时间：2018-10-12 10:43
【摘要】：随着我国高铁技术的迅速发展,深埋长大隧道的设计应用日益增多,而这些隧道常常需要穿越一些不良地质、岩体破碎和岩性不稳定地区,在施工过程中会因开挖、爆破等外力作用产生扰动,导致原本受力平衡的岩体应力发生重新分配,在应力重分配的过程中应力会通过弹性波的形式释放出来,即声发射现象。声发射源产生的信号包含了岩体破裂点位置、释放能量大小、规模等有关岩体损伤程度的信息。因此可以通过分析声发射信号研究岩体损伤的演化规律。而其中最受关心的是岩体受扰动的位置,也就是声发射源的位置。通过确定声发射源的位置达到对整个岩体的稳定性评价的目的。本文介绍了声发射技术的理论基础、常用的定位方法及主要应用领域,总结了声发射特性并分析了影响声发射定位精度的主要因素。针对现有定位软件仅根据单一声发射事件的P波进行定位的不足,提出了结合概率统计中的变异系数用S波对两个连续发生的声发射源进行定位的方法,主要研究内容有：1、利用有限元数值模拟方法模拟连续产生的两个声发射源的波场,直观的揭示了两个连续声发射源产生的波场传播特征。2、岩石声发射波场是包含P波,S波和面波及来自各个岩层分界面产生的干扰波构成的复杂波场。数值模拟的结果表明P波和S波经过界面反射和折射以后,产生的各种波型对第二个声发射源产生的P波影响较大,S波影响较小。基于能量、幅值关系,提出了利用具有强能量、强幅值的横波对连续产生的两个声发射源定位。3、连续产生的两个声发射源的波场经过相互干涉、重叠会导致原本振幅较小的波型振幅变大,如果直接拾取振幅较大的S波进行定位可能会导致定位不准。针对这种情况,引入概率统计中的变异系数对每组声发射源定位结果进行判定,筛除定位偏差较大的定位点。本文的研究为利用S波初至到时实现对连续产生的两个声发射源进行定位提供了理论基础,该方法有效的解决了连续发生的两个声发射源所产生的波场之间相互干扰情况下的定位。对于岩石大规模的声发射事件定位,预测岩体损伤区域和演化规律具有重要的现实意义。
[Abstract]:With the rapid development of high-speed railway technology in China, the design and application of deep buried long tunnels are increasing day by day, and these tunnels often need to pass through some areas of bad geology, rock mass fragmentation and unstable lithology, which will be excavated during construction. In the process of stress redistribution, the stress will be released in the form of elastic wave, that is, acoustic emission phenomenon. The signals generated by acoustic emission sources contain information about rock mass damage degree, such as the location of rock mass rupture point, the magnitude of energy released and the scale of rock mass damage. Therefore, the evolution of rock mass damage can be studied by analyzing acoustic emission signals. The most important concern is the position of rock mass disturbed, that is, the position of acoustic emission source. The stability of the whole rock mass is evaluated by determining the position of acoustic emission source. This paper introduces the theoretical basis of acoustic emission technology, common positioning methods and main application fields, summarizes the characteristics of acoustic emission and analyzes the main factors that affect the accuracy of acoustic emission positioning. In order to solve the problem that the existing localization software is only based on the P-wave of a single acoustic emission event, a method of locating two continuous acoustic emission sources using S-wave combined with the variation coefficient in probability and statistics is proposed. The main research contents are as follows: 1. The wave field of two continuous acoustic emission sources is simulated by the finite element numerical simulation method. The propagation characteristics of wave field generated by two continuous acoustic emission sources are revealed intuitively. 2. The wave field of rock acoustic emission is a complex wave field consisting of P wave, S wave and surface wave, which are composed of interference waves from the interface of various strata. The results of numerical simulation show that after the reflection and refraction of the interface between P wave and S wave, the different wave patterns have a great influence on the P wave produced by the second acoustic emission source, and the influence of S wave is relatively small. Based on the relation of energy and amplitude, it is proposed that the S-wave with strong energy and strong amplitude can be used to locate the two continuously generated acoustic emission sources. 3. The wave fields of the two continuously generated acoustic emission sources are interfered with each other. The overlap will cause the amplitude of the wave type with small amplitude to become larger, and if the S wave with larger amplitude is directly picked up for localization, it may lead to inaccurate localization. In view of this situation, the variation coefficient in probability and statistics is introduced to judge the localization results of each group of acoustic emission sources, and the location points with large localization deviation are screened out. The research in this paper provides a theoretical basis for the localization of two continuously generated acoustic emission sources by using the first arrival time of S wave. This method can effectively solve the problem of mutual interference between two acoustic emission sources. It is of great practical significance to predict the damage area and evolution law of rock mass for large-scale acoustic emission event location.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U452;TU45
本文编号：2265814
[Abstract]:With the rapid development of high-speed railway technology in China, the design and application of deep buried long tunnels are increasing day by day, and these tunnels often need to pass through some areas of bad geology, rock mass fragmentation and unstable lithology, which will be excavated during construction. In the process of stress redistribution, the stress will be released in the form of elastic wave, that is, acoustic emission phenomenon. The signals generated by acoustic emission sources contain information about rock mass damage degree, such as the location of rock mass rupture point, the magnitude of energy released and the scale of rock mass damage. Therefore, the evolution of rock mass damage can be studied by analyzing acoustic emission signals. The most important concern is the position of rock mass disturbed, that is, the position of acoustic emission source. The stability of the whole rock mass is evaluated by determining the position of acoustic emission source. This paper introduces the theoretical basis of acoustic emission technology, common positioning methods and main application fields, summarizes the characteristics of acoustic emission and analyzes the main factors that affect the accuracy of acoustic emission positioning. In order to solve the problem that the existing localization software is only based on the P-wave of a single acoustic emission event, a method of locating two continuous acoustic emission sources using S-wave combined with the variation coefficient in probability and statistics is proposed. The main research contents are as follows: 1. The wave field of two continuous acoustic emission sources is simulated by the finite element numerical simulation method. The propagation characteristics of wave field generated by two continuous acoustic emission sources are revealed intuitively. 2. The wave field of rock acoustic emission is a complex wave field consisting of P wave, S wave and surface wave, which are composed of interference waves from the interface of various strata. The results of numerical simulation show that after the reflection and refraction of the interface between P wave and S wave, the different wave patterns have a great influence on the P wave produced by the second acoustic emission source, and the influence of S wave is relatively small. Based on the relation of energy and amplitude, it is proposed that the S-wave with strong energy and strong amplitude can be used to locate the two continuously generated acoustic emission sources. 3. The wave fields of the two continuously generated acoustic emission sources are interfered with each other. The overlap will cause the amplitude of the wave type with small amplitude to become larger, and if the S wave with larger amplitude is directly picked up for localization, it may lead to inaccurate localization. In view of this situation, the variation coefficient in probability and statistics is introduced to judge the localization results of each group of acoustic emission sources, and the location points with large localization deviation are screened out. The research in this paper provides a theoretical basis for the localization of two continuously generated acoustic emission sources by using the first arrival time of S wave. This method can effectively solve the problem of mutual interference between two acoustic emission sources. It is of great practical significance to predict the damage area and evolution law of rock mass for large-scale acoustic emission event location.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U452;TU45
【参考文献】
相关期刊论文 前10条
1 梁正召,唐春安,黄明利,傅宇方;岩石破裂过程中声发射模式的数值模拟[J];东北大学学报;2002年10期
2 刘培洵;刘力强;陈顺云;扈小燕;;实验室声发射三维定位软件[J];地震地质;2007年03期
3 邹银辉,文光才,胡千庭,许进鹏;岩体声发射传播衰减理论分析与试验研究[J];煤炭学报;2004年06期
4 徐海明;;诺特方程组及佐普里兹方程组问题讨论[J];石油地球物理勘探;1990年02期
5 杨绍国,周熙襄;Zoeppritz方程的级数表达式及近似[J];石油地球物理勘探;1994年04期
6 徐长航;刘立群;陈国明;;钢制试件拉伸断裂及疲劳开裂声发射特征分析[J];中国石油大学学报(自然科学版);2009年05期
7 法林;张雯;孙继刚;丁鹏飞;张学良;李西刚;王淑明;马哲;岳伏生;;岩石界面上的反射/折射系数的研究与应用Ⅱ:SV-波和SH-波入射的情况[J];石油仪器;2013年04期
8 沈功田,耿荣生,刘时风;声发射源定位技术[J];无损检测;2002年03期
9 胡新亮,马胜利,高景春,刘力强,刁桂苓,宋富喜,刘胜国;相对定位方法在非完整岩体声发射定位中的应用[J];岩石力学与工程学报;2004年02期
10 陈炳瑞;冯夏庭;肖亚勋;明华军;张春生;侯靖;褚卫江;;深埋隧洞TBM施工过程围岩损伤演化声发射试验[J];岩石力学与工程学报;2010年08期
相关博士学位论文 前3条
1 康玉梅;基于小波分析的岩石类材料声发射源定位方法研究[D];东北大学;2009年
2 刘国华;声发射信号处理关键技术研究[D];浙江大学;2008年
3 王朝令;隧道地震超前预报中波场分离与反演方法的数值模拟研究[D];西南交通大学;2012年
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