地下工程岩爆及其风险评估综述     

周青春  李海波  杨春和 《岩土力学》2003,(Z2)

根据国内外的研究成果对岩爆进行了数学描述,结合岩性及地质条件、应力条件讨论了发生岩爆的内、外因条件,据此,对岩爆进行了预测。指出岩爆并非单一因素导致的事件,而是典型的多种因素综合作用的结果。因此,在岩爆预测时,应根据其发生的条件,采用综合判别准则。  相似文献   

Improvements in mining induced microseismic source locations at the Lucky Friday mine using an automated whole-waveform analysis system     

Douglas A. Dodge  Kenneth F. Sprenke 《Pure and Applied Geophysics》1992,139(3-4):609-626

For years, severe rockburst problems at the Lucky Friday mine in northern Idaho have been a persistent safety hazard and an impediment to production. An MP250 based microseismic monitoring system, which uses simple voltage threshold picking of first arrivals, has been used in this mine since 1973 to provide source locations and energy estimates of seismic events. Recently, interest has been expressed in developing a whole waveform microseismic monitoring system for the mine to provide more accurate source locations and information about source characteristics. For this study, we have developed a prototype whole-waveform microseismic monitoring system based on a 80386 computer equipped with a 50 kHz analog-digital convertor board. The software developed includes a data collection program, a data analysis program, and an event detection program. Whole-waveform data collected and analyzed using this system during a three-day test have been employed to investigate sources of error in the hypocenter location process and to develop an automatic phase picker appropriate for microseismic events.Comparison of hypocenter estimates produced by the MP250 system to those produced by the whole-waveform system shows that significant timing errors are common in the MP250 system and that these errors caused a large part of the scatter evident in the daily activity plots produced at the mine. Simulations and analysis of blast data show that analytical control over the solutions is strongly influenced by the array geometry. Within the geophone array, large errors in the velocity model or moderate timing errors may result in small changes in the solution, but outside the array, the solution is very sensitive to small changes in the data.Our whole-waveform detection program picks event onset times and determines event durations by analysis of a segmented envelope function (SEF) derived from the microseismic signal. The detection program has been tested by comparing its arrival time picks to those generated by human analysis of the data set. The program picked 87% of the channels that were picked by hand with a standard error of 0.75 milliseconds. Source locations calculated using times provided by our entire waveform detection program were similar to those calculated using hand-picked arrival times. In particular, they show far less scatter than source locations calculated using arrival times based on simple voltage threshold picking of first arrivals.  相似文献   

Analytical and Numerical Study on the Pillar Rockbursts Mechanism   总被引：3，自引：1，他引：3  

S. Y. Wang  K. C. Lam  S. K. Au  C. A. Tang  W. C. Zhu  T. H. Yang 《Rock Mechanics and Rock Engineering》2006,39(5):445-467

Summary. Based on cusp-type catastrophe theory, a sample rock–rock model for studying the pillar rockburst mechanism is presented in this paper. It is shown that the stiffness ratio, K, of the roof and floor to the pillar plays an important role in the outbreak of instability. Additionally, simple formulae for the deformation jump and the energy release are derived. Based on the assumption that there exists a proportional relationship between the number of microseismic events and microfractured elements, the theoretical microseismic event rate produced by the double rock sample, loaded in series under uniaxial compression, is obtained. Using a newly developed numerical code, RFPA^2D, the progressive failure process and associated microseismic behavior of the twin rock samples are simulated, which shows that the spatial distribution of microseismic events develops progressively from disorder at the initial loading stage to order prior to the main shock. The numerically simulated results also confirm that a soft roof and floor promote an unstable failure or collapse of pillars, while a stiff roof and floor can lead to a stable failure of pillars. Additionally, the simulated results reproduce the deformation jump and the energy release that occur during a pillar rockburst. It is demonstrated that the proposed model properly simulates the pillar failure process.  相似文献   

滇藏铁路丽江玉峰寺隧道围岩岩爆刚度判据     

刘景儒  张永双  吴树仁  李东林  刘成田 《地质通报》2007,26(6):748-755

从最小能量原理出发,探讨隧道围岩岩爆的刚度判据问题,并应用于滇藏铁路玉峰寺隧道工程。在滇藏铁路玉峰寺隧道代表性围岩岩样全应力应变刚压实验分析的基础上,结合地应力测量资料和数值模拟,分析玉峰寺隧道3种岩性不同围压条件下的变形破坏过程,得到隧道塑性破坏岩体和弹性岩体的刚度曲线,利用刚度判据,分析评价玉峰寺隧道3类岩体发生岩爆的危险性,玄武岩岩爆烈度最高,灰岩次之,砂岩最低,为隧道工程设计提供了参考依据。  相似文献   

邢台石膏矿矿震孕育过程及警示   总被引：5，自引：0，他引：5  

闻军  勾宪斌  赵京轶 《地震地磁观测与研究》2007,28(2):36-40

2005年11月6日河北邢台县石膏矿发生了矿难,本文使用首都圈台网记录的从当日09时小矿震初始活动到19时36分矿难发生的所有矿震波形数据,根据对矿震活动序列分析,对不同时段矿井顶板受到的张力及剪切力作用进行了研究,论述这一次矿难的孕育过程和发生机理,分析这一次矿震造成重大人员伤亡原因,诠释矿山(井)安全监测预警系统和安全意识的重要性.  相似文献   

循环扰动和高温作用下砂岩的岩爆倾向性及破坏特征研究     

张平  任松  张闯  吴斐  隆能增  李凯鑫 《岩土力学》2023,(3):771-783

为了揭示循环扰动和高温影响下砂岩的岩爆机制,开展了循环扰动和高温作用下砂岩单轴压缩试验和CT扫描试验,研究了不同条件下砂岩的力学特性、岩爆倾向性及破坏特征,探讨了岩爆倾向性与破坏特征的关系。研究结果表明：循环扰动和高温对砂岩的力学性能及岩爆倾向性影响效果显著;无循环扰动砂岩的单轴抗压强度、弹性模量及岩爆倾向性随温度的升高呈先增加后降低的趋势,200℃为该类砂岩的阈值温度,受循环扰动砂岩的力学特性及岩爆倾向性随温度的上升而降低;而砂岩的力学特性及岩爆倾向性随循环应力幅值增加而下降;随着循环应力幅值和温度的增加,砂岩破坏模式由劈裂破坏向剪切破坏转变,同时砂岩的岩爆倾向性与裂隙三维分形维数呈良好的负相关关系;此外,高温对砂岩的力学性能、岩爆倾向性及破坏程度影响效果强于循环扰动。研究结果可为高温工程岩爆防治提供理论依据和工程参考价值。  相似文献   

Buckling mechanism of pillar rockbursts in underground hard rock mining     

J. Deng  D. S. Gu 《Geomechanics and Geoengineering》2018,13(3):168-183

The objective of this paper is to investigate the buckling mechanism of pillar rockbursts in underground hard rock mines from an innovative point of view. By considering rockbursts as a buckling (instability) problem of structures, rockbursts are classified into three categories: induced rockburst, triggered rockburst and inherent rockburst, in accordance with the magnitude of the dynamic stimulation force from large to null. Rigorous mathematical models are set up for these three rockbursts. For induced and triggered rockbursts, mechanism of parametric resonance is found and perturbation effect is observed. For inherent rockbursts, the condition of critical static loads is obtained. Various examples of rockbursts in Dongguashan Copper Mine are analysed. The limitations of the approach are addressed. Contrary to conventional methods where only rock materials or rock specimens were used for investigation of rockbursts, this study attaches more attention on the structural effect on rockbursts, which may appeal to practising engineers.  相似文献   

不同围压条件下的圆形巷道岩爆过程模拟     

王学滨  潘一山  王玮 《地震学刊》2009,(6):597-603

利用FLAC模拟了不同围压条件下圆形巷道的岩爆过程。为了模拟巷道开挖,利用编写的FISH函数删除巷道内部的单元。岩石服从摩尔库仑剪破坏与拉破坏复合的破坏准则,破坏之后呈现应变软化-理想塑性行为。模拟结果表明：当围压较低时,剪切应变集中区域呈圆环状,围岩能保持稳定,不出现剪切带;当围压增加到一定程度时,围岩中出现了“狗耳”形的V形坑,发生岩爆,但围岩也还能保持稳定;当围压进一步增加时,围岩中出现了多条狭长的剪切带,巷道的整个断面均遭到了破坏,发生强烈的岩爆。随着围压的增加,V形岩爆坑变大、变深,剪切带花样的对称性变差;在高围压时,剪切带花样与塑性力学中的滑移线网有类似之处。  相似文献   

岩爆等级判定的距离判别分析方法及应用   总被引：2，自引：1，他引：1  

王吉亮  陈剑平  杨静  阙金声 《岩土力学》2009,30(7):2203-2208

将距离判别分析方法应用于岩爆等级判定问题。选用洞室围岩最大的切向应力σθ、岩石单轴抗压强度σc、抗拉强度σt、岩石弹性能量指数Wet作为岩爆等级判定的距离判别分析模型判别因子,以工程中实际岩爆情况及数据作为训练样本,进行分析计算,建立岩爆等级判定的距离判别分析模型。运用该分析模型对国内外工程实际岩爆情况进行判定,判别结果与工程实际完全相符。将该模型应用到诸（暨）永（嘉）高速公路括苍山隧道工程的岩爆情况预测中,判别结果与实际情况相符。研究表明,岩爆等级判定的距离判别分析方法,判别能力强,误判率低,是解决岩爆等级判定的一条有效途径。  相似文献   

基于剪切梁层间失效模型的断层冲击地压分析   总被引：1，自引：0，他引：1  

赵扬锋  潘一山  于海军 《岩土力学》2007,28(8):1571-1576

将剪切梁层间失效模型用于分析断层冲击地压的发生,在不考虑断层的弹性时对断层冲击地压进行了解析分析,得到了剪切梁的位移和应力分布规律和断层冲击地压发生时撕开裂纹长度和临界载荷。分析了撕开裂纹长度和临界载荷与各种力学参数之间的关系。研究结果表明：当采深越大,剪切梁的剪切弹性模量越小,剪切梁厚度越厚,断层带剪切软化模量越大;断层带厚度、滑动摩擦系数、剪应力峰值强度越小时,断层冲击地压容易发生。采深、剪切梁的剪切弹性模量、断层带剪切软化模量、剪应力峰值强度、断层带厚度这些参数对断层冲击地压的发生影响较大。其结果为预测、防治断层冲击地压提供了理论依据。  相似文献