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Search Results: 1 - 10 of 466587 matches for " <br>李夕兵 "
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STATISTICAL PROBABILITY METHOD FOR THE EXTENSION OF A DISCONTINUOUS SURFACE IN ROCK MASS AND ITS APPLICATIONS
岩体弱面延展性的概率估算及其应用

Liu Aihua,Li Xibing,<br>刘爱华,
岩石力学与工程学报 , 1997,
Abstract: 岩体材料常被各类构造弱面所切割分离,这些弱面的特性严重影响甚至控制着岩体材料的力学及水力学性能。正确地对岩体中各类弱面的空间分布进行描述,对研究不同结构岩体的破坏机制,以及对合理地处理和解决岩体工程中的实际问题都具有重要意义。文章重点介绍了描述弱面的重要参数之一的弱面延展性的概率估算方法及其应用。
EXPERIMENTAL STUDIES OF MECHANICAL PROPERTIES OF TWO ROCKS UNDER DIRECT COMPRESSION AND TENSION
2种岩石直接拉压作用下的力学性能试验研究

LI C CHARLIE,<br>地元,,LI C CHARLIE
岩石力学与工程学报 , 2010,
Abstract: 利用Instron1342液压伺服机对2种典型硬岩和软岩试样进行单轴试验,包括单轴压缩试验和直接拉伸试验,研究这两种岩石在直接拉压作用下的力学性能,对比2种岩石的单轴抗压强度和单轴拉伸强度。试验过程中监测岩石试样的轴向应变和水平应变,并记录岩石试样的声发射特征,得到2种岩石在单轴拉压下的应力–应变曲线和声发射计数率曲线,对比2种岩石在单轴拉压下的声发射变化规律。试验发现,直接拉伸下2种岩石在加载初期较大范围内基本无声发射事件发生,直到破坏前声发射事件数才突然增大。讨论2种岩石在不同加载模式下的弹性模量和泊松比变化关系,发现单轴压缩下,硬岩的弹性模量随载荷变化先增大而后趋于稳定,当载荷超过单轴抗压强度的80%时又变小;而单轴拉伸下,硬岩的弹性模量初始较大,随后随着载荷增大而逐渐减小。单轴压缩下2种岩石的泊松比为0.2~0.3,而单轴拉伸下岩石的泊松比很小,几乎可以忽略。比较2种岩石的破坏角、内摩擦角以及黏聚力,讨论2种岩石在直接拉压作用下的不同破坏模式。利用三维表面形貌扫描仪对直接拉伸试样的破坏断面进行三维扫描,得到破坏面细观结构图和裂纹面表面粗糙度曲线。
Fractal Property of Granite Failure under Coupled Static-Dynamic Load
动静组合加载作用下花岗岩破碎的分形特征

WANG Qi-sheng,LI Xi-bing,<br>王其胜,
实验力学 , 2009,
Abstract: 在分离式霍普金森压杆实验装置上进行了花岗岩破坏的动静组合加载实验.通过对受载后岩样破碎块度进行筛分统计,得到了该加载条件下岩石破碎的粒度分布.在此基础上,通过理论计算公式,进一步得到了相应的破碎分形维数,分别探讨了静载荷和冲击载荷对分维数的影响.结果表明,动静组合加载作用下花岗岩破碎分维值在2.0~2.8之间;相同静载不同动载下,花岗岩的破碎分维值与试样的应变率有关,随应变率增大而增大;而在相同冲击动载下,静载荷变化对分形维数的影响不大.
STUDY ON FRACTAL GRADATION OF TAILINGS AND KNOWLEDGE BANK OF ITS CEMENTING STRENGTH
尾砂分形级配与胶结强度的知识库研究

LIU Zhi-xiang,LI Xi-bing,<br>刘志祥,
岩石力学与工程学报 , 2005,
Abstract: Characteristics of tailings gradation are studied by using fractal theory. Experimental data about the fractal gradations of tailings material and their cementing strength from a lot of mines are analyzed. Neural network is used to establish the model of knowledge bank which embodies the relations between strengths of cemented tailings and content of cement,consistence,fractal dimension of porosity and correlation coefficient of fractal dimension. Combining grading method with chaotic optimization,the neural network model achieves rapid training and avoids local minimum when there are a lot of samples to be trained. Research results show that the strengths of cemented tailings increase with the decrease of fractal dimension of porosity and with the increase of the correlation coefficients of fractal dimension. Because fractal dimension of porosity and its correlation coefficient embody the global distribution information of tailing granule,they can be used as a standard of rationality of gradation. According to gradation of tailings,the knowledge bank model can predict the strengths of cemented tailings in different contents of cement or consistence,and guide filling design in mine.
A DISTANCE DISCRIMINANT ANALYSIS METHOD FOR PREDICTION OF POSSIBILITY AND CLASSIFICATION OF ROCKBURST AND ITS APPLICATION
岩爆发生和烈度分级预测的距离判别方法及应用

GONG Fengqiang,LI Xibing,<br>宫凤强,
岩石力学与工程学报 , 2007,
Abstract: 岩爆是深部高地应力区岩石地下工程中的主要工程地质灾害之一,对其发生的可能性及其烈度分级的预测是工程建设过程中所必须解决的重大问题。基于距离判别分析理论,建立岩爆发生和烈度分级预测的距离判别分析模型。选取影响岩爆的主要因素如最大切向应力σθ、小单轴抗压强度σc、单轴抗拉强度σt和弹性能量指数Wet,并把σθ/σc,σc/σt和Wet作为判别因子建立岩爆预测的距离判别分析模型,利用国内外一些重大深部岩石工程实例作为学习的样本进行训练。经过训练后的模型回判估计的误判率为0。利用该模型对国内西康铁路秦岭隧道工程和铜陵冬瓜山深埋硬岩矿山的岩爆情况进行预测,结果与实际情况符合较好,说明该模型在研究岩爆发生可能性及烈度分级预测中具有良好的实用性和有效性。该方法可为深部地下工程岩爆发生可能性及其烈度分级预测提供一种新思路。
CONSTITUTIVE MODEL OF ROCK UNDER COUPLED STATIC-DYNAMIC LOADING WITH INTERMEDIATE STRAIN RATE
中应变率下动静组合加载岩石的本构模型

LI Xibing,ZUO Yujun,MA Chunde,<br>,左宇军,马春德
岩石力学与工程学报 , 2006,
Abstract: The importance of study on constitutive model of statically loaded rock under dynamic loading is expounded,and the methods of dynamic constitutive model are classified according to the current studying.By way of combining statistic damage model and viscoelastic model,uniaxial and triaxial constitutive models of statically loaded rock under dynamic loading(coupled static-dynamic constitutive model) with intermediate strain rate are established.The verification experiment on 1D coupled static-dynamic constitutive model under different static loadings is designed and performed.It is found that there is a good agreement between experimental stress-strain curves and theoretical stress-strain curves.The 3D theoretical stress-strain curves under different strain rates are verified by test data.
ANALYTICAL ALGORITHM TO ESTIMATE TENSILE MODULUS IN BRAZILIAN DISK SPLITTING TESTS
巴西圆盘劈裂试验中拉伸模量的解析算法

GONG Fengqiang,LI Xibing,ZHAO J,<br>宫凤强,,ZHAO J
岩石力学与工程学报 , 2010,
Abstract: 提出巴西圆盘劈裂试验中拉伸模量的解析算法。结合圆盘对心受力的理论弹性解和实际试验过程中便于测量的物理参数,基于微积分的原理,通过对试样中心垂直加载方向上每一点拉应变的积分,可以得到该方向上总的变形量,进而推导出岩石拉伸模量和总位移变形量之间的定量关系式。该关系式包含加载力、试样直径、试样厚度、岩石泊松比和试样中心垂直加载方向上总位移变形量5个物理量,其意义明确,运用简便,可为求解巴西劈裂试验拉伸模量提供一种新的方法。
SEISMIC MULTI-FRACTAL CHARACTERISTICS IN MINES AND SEISMICITY PREDICTION
矿山地震活动多重分形特性与地震活动性预测

KWXIA,<br>唐礼忠,K.W.XIA,
岩石力学与工程学报 , 2010,
Abstract: 矿山地震活动可直接揭示矿山岩体活动状态和危险性水平。利用冬瓜山铜矿矿山地震监测数据,采用广义关联积分计算地震震源空间分布的分形维,利用Gutenberg-Richter关系中的b值与地震事件能量分形维关系计算地震能量分形维,并结合开采活动及矿山结构特征,研究矿山地震活动的分形结构特性和时域谱特征。研究结果表明,矿山地震活动具有多重分形特性,它与开采活动及矿山结构特点之间存在相关性;只有当计算空间区域的地震分形结构较均匀时,其分形维才能有效应用于地震活动性预测。这些空间通常对应于采掘类型少和结构单一的空间区域。地震空间分布分形维 反映了矿山地震活动状态,其时域谱具有较好的主震前兆特征,可以作为地震预测的参数; 时域谱的地震前兆性较差,较难预测主震。
EFFECTS OF SINGLE JOINT WITH NONLINEAR NORMAL DEFORMATION ON P-WAVE PROPAGATION
非线性法向变形节理对弹性纵波传播的影响

WANG Weihua,LI Xibing,ZUO Yujun,<br>王卫华,,左宇军
岩石力学与工程学报 , 2006,
Abstract: The linear displacement discontinuity model is derived from elastic displacement functions of wave, and then a nonlinear displacement discontinuity model is established by introducing the equivalent displacement hypothesis. Based on the established model, the analytic resolution of transmitted and reflected coefficients is obtained when the normal incident P-wave propagates to the nonlinear normal deformative joint. The effects of parameters such as initial joint stiffness, quantitative ratio of joint closure to allowable joint closure and incident frequency of wave on transmitted and reflected coefficients are investigated. By comparison with the published numerical results, it is found that the analytic results agree well with the numerical calculations.
APPLICATION OF DISTANCE DISCRIMINANT ANALYSIS METHOD TO CLASSIFICATION OF ENGINEERING QUALITY OF ROCK MASSES
距离判别分析法在岩体质量等级分类中的应用

GONG Fengqiang,LI Xibing,<br>宫凤强,
岩石力学与工程学报 , 2007,
Abstract: Based on the principle of Mahalanobis distance discriminant analysis,a classification model of engineering quality of rock masses is established,including six indexes reflecting the engineering quality of rock masses:uniaxial compressive strength,P-wave velocity in rock,volumetric joint countr,oughness coefficients of joints,weathering coefficients and permeability coefficient of joints.Linear discriminant functions are obtained through training a large set of expansive samples.The results show that the classification model of distance discriminant analysis has excellent performance,high prediction accuracy;and can be used in practical engineering.
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