曲石湾滑坡体成因分析及防治措施研究   总被引：4，自引：1，他引：4  

吕义清  王银梅 《中国地质灾害与防治学报》2001,12(1):27-29

滑坡的形成对周围环境造成很大的影响，并严重制约地方经济发展，威胁人民生命财产安全，因此，滑坡成因及防治措施的研究具有重要意义。本文通过实际资料，分析曲石湾滑坡体的形成机理，有针对性的提出曲石湾滑坡的防治措施。  相似文献   

绿片岩力学性质的实验研究     

顾芷娟  潘裕生  周勇  陶京玲  刘成龙 《现代地质》2001,15(4):450-452

绿片岩的力学实验表明 ,在围压 45 0MPa条件下 ,岩石约于 45 0℃开始塑性变形。温度升至 5 5 0℃时变形加剧 ,原来直径为 10mm、高 2 0mm的均匀圆柱体变成直径为 10 8mm、高 17 4mm、中部变粗的不规则柱体。这一结果为解释青藏高原的地壳加厚提供了一定的实验依据  相似文献   

塔里木北部地区岩石物性参数测试和区域层滑系统的确定   总被引：7，自引：0，他引：7       下载免费PDF全文

孙岩  贾承造 《地球物理学报》1996,39(5):660-671

为了定量地研究塔里木北部地区区域的层次结构．拆离构造，特别是同油气地质、圈闭构造密切相关的沉积盖层中的层滑倾滑和推覆滑覆等各种构造的形成机制，对该区沉积盖层进行了较系统的岩石物性和岩石力学标本采集和测试（包括三轴参照实验）．依其参数结构特点和地质、物探资料，划分出４套７层区域性层滑系统，并与研究程度较高的中、下扬子区的物性参数、岩性组合和构造特征进行综合对比．最后还进一步阐明了塔里木北部地区特征的前列式冲断构造和含油气局部构造等，均受到这７层区域层滑系统的制约．  相似文献   

强震地面运动的解析解     

范家参  费维水 《地震研究》1996,19(1):95-118

本文用具有非线性Ｒａｙｌｅｉｇｈ阻尼的断裂动力学的控制方程组或方程来研究水平强震地面运动或垂直强震地面运动，并得出其解析解，数值计算结果显示，本文得出的结果与任意选择的两个强震记录是很相似的。  相似文献   

Fractures: Finite-size scaling and multifractals   总被引：1，自引：0，他引：1  

L. J. Pyrak-Nolte  L. R. Myer  D. D. Nolte 《Pure and Applied Geophysics》1992,138(4):679-706

The distributions of contact area and void space in single fractures in granite rock have been determined experimentally by making metal casts of the void spaces between the fracture surfaces under normal loads. The resulting metal casts on 52 cm diameter core samples show a complex geometry for the flow paths through the fracture. This geometry is analyzed using finite-size scaling. The spanning probabilities and percolation probabilities of the metal casts are calculted as functions of observation scale. Under the highest stresses of 33 MPa and 85 MPa there is a significant size-dependence of the geometric flow properties for observation scales smaller than 2 mm. Based on this data, the macroscopic percolation properties of the extended fracture can be well represented by relatively small core samples, even under normal stresses larger than 33 MPa. The metal casts also have rich multifractal structure that changes with changing stress.  相似文献   

关于固结度计算的一点看法     

方玉树 《水文地质工程地质》1993,20(5):24-25

通过探寻渗透系数、压缩系数(或体积压缩系数)与孔隙比在固结过程中的变化规律来确定固结系数与固结时间的关系并将其用于固结度计算是无益的,原因在于固结度计算公式只在固结系数为常数时才成立。  相似文献   

The remote sensing observation in experiments of rock failure and the beginning of remote sensing rock mechanics     

Nai-Guang Geng  Cheng-Yu Cui  Ming-De Deng 《地震学报(英文版)》1993,6(4):971-980

The remote sensing observational study for infrared radiation of rocks was proceeded during the loading on rocks until failure. The major instruments used in experiments were transient spectrum apparatus, intelligent spectrum apparatus, infrared radiation thermometer, infrared spectrum radiometer, and infrared thermal imaging system. The experiments for 26 kinds of rocks were made. The studies show that infrared radiation temperature of rocks increases along with increasing of stress. The amplitude of infrared radiation spectrum of rocks also increases along with increasing of stress. The observational results of infrared thermal imaging of rocks are consistent with infrared radiation temperature. Before formation of major faults for some rocks, the belt-shape thermal imaging of temperature anomaly displaies in position of future major faults. This study has led the new technology of remote sensing into rock mechanics and tend to establish a new field in rock mechanics — remote sensing rock mechanics (or remote sensing rock physics). The application of remote sensing rock mechanics in prediction of earthquake and rock burst, and in measurement of stress field in rock mass is expected. The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,14, Supp., 645–652, 1992. Jin-Shen HAO, Ji-Han LI, Xiao-Hong LIU, Yi-Qiao ZHI, Jin-Kai ZHANG, Yong-Hong Lü, Yi LIU, Yun-Shen YU, He ZHANG, Quan-Quan JI, Xiao-Fan ZHU and Ning CHEN took part in this work. This subject is supported by the Chinese Joint Seismological Science Foundation (91006). Work of Institute of Geophysics, SSB (93A0009).  相似文献   

Hydrofracture mechanisms in rock during pressure grouting     

H. Y. Wong  I. W. Farmer 《Rock Mechanics and Rock Engineering》1973,5(1):21-41

Summary Hydrofracture Mechanisms in Rock During Pressure Grouting. The paper examines the basic meachnisms controlling the initiation of fractures in rocks and layered soils during pressure grouting, and their subsequent propagation into the ground mass. Previous analyses of fracture initiation have tended to concentrate on simplified models in which the ground is treated as an impervious elastic or Mohr-Coulomb continuum. The present method allows for the porous or fissured nature of the ground by considering the effect of seepage forces induced by the pore pressure gradient. The effect is quantified by use of a parameterN such that the ratio of fluid force used in expanding the injection hole, to that used in forcing fluid through void spaces, isN to (1—N).Analysis of hydrofracture propagation is based on stress analysis of a borehole in an elastic continuum, the propagating fracture zone around the borehole being represented as a non-elastic material governed by the Mohr-Coulomb failure criterion. This is supplemented by an energy approach which equates the energy supplied to the ground from the injection pump, with the energy stored in the ground and the energy necessary to fracture it.

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Zusammenfassung Brucherscheinungen im Fels bei Verprearbeiten. In der Arbeit wird der grundlegende Mechanismus untersucht, welcher bei Verpreßarbeiten in Fels und geschichtetem Boden zur Einleitung und Ausbreitung von Brüchen führt. Frühere Untersuchungen des Bruchbeginns stützten sich im wesentlichen auf vereinfachte Modelle, in denen der Untergrund als undurchlässiges Kontinuum angesehen wird, das entweder elastisch ist oder der Mohr-Coulombschen Bruchbedingung genügt. Die neue Methode berücksichtigt dagegen eine Porosität oder Klüftung des Untergrundes durch Ansatz der vom strömenden Medium auf das Gebirge ausgeübten Belastung. Diese Belastung wird aufgeteilt in einen Druckverlust an der Bohrlochwand (gleich ParameterN mal Verpreßdruck) und die entsprechende, über den gesamten durchströmten Bereich verteilte Belastung.Die Untersuchung der Bruchausbreitung geht von der Spannungsermittlung um ein Bohrloch in einem elastischen Kontinuum aus, wobei in der sich ausbreitenden Bruchzone um das Bohrloch herum nichtelastisches Material angenommen wird, das dem Mohr-Coulombschen Bruchkriterium genügt. Zur Ergänzung dient eine Energie-Betrachtung, bei der die von der Injektionspumpe abgegebene Energie gleichgesetzt wird der im Untergrund gespeicherten Energie und der aufgewendeten Brucharbeit.

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Résumé Les mécanismes de la fracturation hydraulique dans les roches pendant les injections sous pression. Le mémoire examine les mécanismes fondamentaux qui gouvernent l'initiation des ruptures dans les roches et les sols stratifiés, au cours des injections et leur propagation dans les massifs. Les analyses antérieures de l'initiation de la rupture, se sont concentrées sur des modèles simplifiés où l'on considérait la roche comme un milieu élastique et imperméable, ou comme un milieu de Mohr-Coulomb. La présente méthode admet que le massif est poreux ou fissuré, en considérant l'action des forces de percolation engendrées par le gradient de pression interstitielle. Cette action est quantifiée par un paramètreN, tel que le rapport de la force du liquide employée à dilater le forage d'injection, à celle employée pour forcer le coulis à travers les vides soitN/(1—N). L'analyse de la propagation des ruptures se base sur l'analyse des contraintes autour d'un forage dans un milieu élastique, alors que la zone de la rupture qui se propage autour du forage est représentée par un milieu non-élastique admettant le critère de rupture de Mohr-Coulomb. Cette analyse est complétée par une approche énergétique, où l'énergie qui est fournie au massif par la pompe d'injection est égalée à l'énergie emmagasinée dans la roche et à l'énergie de rupture.

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Nomenclature A area of new cracks created per unit volume of time t - E total work done by injection fluid - E _i irrecoverable component of energy - E _{i c} work done in fracturing rock or soil - E _{i l} work done to overcome various frictional forces in grouting system - E _{i p} work done to cause plastic deformation of fractured zone - E _{i s} work done to overcome shear strength of fluid during flow - E _{i v} work done to overcome frictional drag between fluid and rock in soil surfaces during flow - E _r recoverable component of energy - E _{r f} elastic strain energy stored in fluid - E _{r s} elastic strain energy stored in rock or soil - h height of overburden - i j 1, 2, 3 - K ₀ coefficient of horizontal earth pressure - k permeability of ground to grout - L length of cylindrical grout source - n rock or soil porosity - p average fluid pressure between timet and (t + t) - p ₀ injection pressure - R radius of grout front - r radial distance from borehole axis - r ₀ radius of borehole - r ₁ radius of fractured zone - S specific surface area of rock or soil - S _T tensile strength of rock or soil - t time - u grout seepage velocity - V volume of grout injected - v volumetric strain - specific surface energy of rock - bulk density of rock or soil - _{i j} ^e elastic strain increment tensor - _{i j} plastic strain increment tensor - v Poisson's ratio - _{i j} average stress tensor in the ground during timet and (t + t) - _R , _T, _Z radial, tangential and vertical stresses induced by grouting - _r , _t , _z radial, tangential and vertical stress around borehole before grouting - grout shear strength - angle of internal friction of rock or soil With 7 Figures  相似文献   

4颗卫星情况的几何优化法修正   总被引：6，自引：0，他引：6  

郑作亚  黄珹  冯初刚  张飞鹏 《天文学报》2003,44(3):310-317

在GPS定位与导航中,用户可以通过选择至少4颗可见卫星的观测,得到测站位置和站钟差信息,卫星相对于测站的几何关系直接影响到定位和导航的精度,考虑用4颗卫星进行定位,在当前有一定的现实意义,在KihaLra等人工作的基础上对四面体的性质进行了深入讨论,推导了4颗可见卫星构成四面体体积的计算公式,实例分析证明该计算公式更合理、更精确。  相似文献   

Atmospheric superrotation?     

E.M Gaposchkin 《Planetary and Space Science》2003,51(6):415-425

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