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991.
Determination of shear strength of conglomerates using a caterpillar D9 ripper and comparison with alternative methods 总被引:1,自引:0,他引:1
J. P. Savely 《Geotechnical and Geological Engineering》1990,8(3):203-225
Summary A method of determining shear strength in Gila Conglomerates at Inspiration Mine (now Cyprus Miami Mine), Arizona, using Caterpillar D9H and D9L rippers is described. The results are compared with data obtained using laboratory direct shear tests — both large and small scale, back analysis and boulder modelling. The significance of scale, particularly relating to boulder size is discussed. 相似文献
992.
A time-dependent linear model on the equatorial beta plane is developed in this paper.Its vertical structure consists of two active layers with equal density and temperature above the thermocline and a quasi-stationary layer with constant density below the thermocline.The results of nurnericat experiments show that the direct influence of heat on the equatorial ocean is much smaller than that of wind stress.Nevertheless,through the tropical ocean-atmosphere interaction,the change of wind stress resulting from the thermal forcing may set a determinant effect on the equilibrium and anomalous development of the ocean-almosphere circulation. 相似文献
993.
994.
NUMERICAL EXPERIMENT OF THE INFLUENCES OF HEAT AND WIND STRESS ON THE EQUATORIAL OCEAN CIRCULATION 总被引:1,自引:0,他引:1 下载免费PDF全文
A time-dependent linear model on the equatorial beta plane is developed in this paper.Its verticalstructure consists of two active layers with equal density and temperature above the thermocline and aquasi-stationary layer with constant density below the thermocline.The results of nurnericat experiments show that the direct influence of heat on the equatorial ocean ismuch smaller than that of wind stress.Nevertheless,through the tropical ocean-atmosphere interaction,the change of wind stress resulting from the thermal forcing may set a determinant effect on the equilibriumand anomalous development of the ocean-almosphere circulation. 相似文献
995.
Tao Zuyu 《Acta Meteorologica Sinica》1994,8(3):337-345
The error distributions of the wind fields retrieved from single and dual-Doppler radar observations are given inthis paper.The results indicate that the error of dual-Doppler retrieval depends on the position in the scan region of thedual-Doppler radar.The error of single-Doppler retrieval by using velocity azimuth processing(VAP)technique de-pends on the angle between the directions of wind and the radar beam.Generally,the winds retrieved from single Doppl-er radar are close to those retrieved from dual-Doppler radar.But,the error distribution of the single-Doppler retrievalis different from the dual-Doppler retrieval.We simulate the retrievals of single Doppler observation by the use of theoutput wind data from a 3-D numerical model of severe convection.The comparison of the simulated single-anddual-Doppler retrievals shows that the VAP may be a suitable technique for the operational analysis of mesoscale windfields.It can also be used as a supplement to wind field retrieval in the field experiment. 相似文献
996.
莫尔-库仑强度理论的修正 总被引:3,自引:1,他引:3
本文对莫尔-库仑(Mohr-Coulomb)强度理论作了重要修正。指出静水应力不仅对材料固有强度,而且对剪切滑移也有影响,从而得到了一个计及中间主应力影响的剪切强度公式。根据断裂力学的分析,该公式可进一步用于材料的断裂强度的计算。 相似文献
997.
SOILSHEARSTRENGTH:ANINDICATORFORERODIBILITYOFTHELOESSSOILSWANGGuiping;WEIZhongpingandZHANGZhiguoAbstract:FieldexperimentSunde... 相似文献
998.
三道溜河地区太古宙岩浆-构造事件 总被引:3,自引:0,他引:3
三道溜河地区处于中朝准地台北东缘,北西起自著名的夹皮沟金矿,南东至四道砬子河,太古宇出露广泛。笔者在此进行1:5万区调时,共发现了六次岩浆-构造事件,由老至新依次为:787角闪辉石岩、岭东片麻岩、大朝阳沟斜长角闪岩、三道溜河TTG岩组、唐胡店沟二长花岗岩、五道砬子河变辉长辉绿岩(发生在元古宙早期,在时空上与太古宇关系密切)。上述事件,表现为基性岩类与酸性岩类交替出现。基性岩事件依次为超基性岩-基性岩-偏碱性基性岩,稀土元素总量由高至低,微量元素Ba、Mn、Zr递增,Pb、Zn递减。酸性岩事件依次为中酸性岩-酸性岩-偏碱性酸性岩,稀土元素的La/Lu、ΣCe/ΣY由低到高,总量变化不大,微量元素Co、Cr、Ni、Cu递减。本区的构造运动与岩浆侵入活动相辅相成,古穹窿构造及北西向韧性剪切带控制了Au、Ag、Cu等矿产的展布。 相似文献
999.
The main characteristics of river flow and grainsize in a bend of the sand bedded meandering river Dommel, The Netherlands, are presented. Measurements were carried out at a relatively low discharge in a sharply curved bend following a long straight reach. In the studied bend, secondary circulation is restricted to the thalweg area; only in the downstream part of the bend it exists over the entire cross-section. Therefore, on the entire pointbar platform, which comprises the larger part of the bend, the median sedimentation diameter of the bedload material is governed by the distribution of the longitudinal components of the bed shear stress only. 相似文献
1000.
华北地区的共轭地震构造带 总被引:10,自引:3,他引:10
本文采用小地震活动图象和4.0级(Ms)以上地震震源机制资料的构造分析方法,得到一幅华北地区震源构造在地面的投影分布图,它显示4条NNE-NE向和1条NWW-NW向地震构造带交切成的共轭剪切构造格架。每条地震构造带又由一系列共轭剪切构造组成。由发生在带内的5个大震序列共轭破裂特征发现,共轭地震构造的孕震与控震作用是地震构造带形成的机制。 相似文献