土建专业外文翻译7.docx

外文翻译problems1 from the data given in figure 4.18,calculate the tangent modulus and poissons ratio for the initial elastic behavior of limestone with3= 2.0mpa.2 a porous sandstone has a uniaxial compressive strength of c=75mpa. the results of a series of triaxial compression tests plotted on shear stress-normal stress axes give a linear coulomb peak strength envelope having a slope of 45odetermine the axial stress at peak strength of a jacketed specimen subjected to a confining pressure of 3= 10mpa. if the jacket had been punctured during the test and the pore pressure had built up to a equal to the confining pressure ,what would the peak axial stress have been?3(a) establish an approximate peak strength envelope for the marble for which the date shown in figure 4.19 were obtained.3(b) in what ways might the observed stress-strain behavior of the specimens have differed had the tests been carried out in a conventional testing machine having a longitudinal stiffness of 2.0 gnm-1? assume that all specimens were 50mm in diameter 100mm long.rock strength and deformability4 a series of laboratory tests on intact specimens of quartzite gave the following mean peak strengths. the units of stress are mpa, and compression is taken as positive.triaxialcompression2=3100100135130160150200180298248435335biaxialtension/compression123000-13-13.521850-13225100022815002102100develop a peak strength criterion for the quartzite for use in underground excavation design. experience has shown that in situ uniaxial compressive strength of the quartzite is one-half the laboratory value.5 a series of triaxial compression tests on specimens of a slate gave the following results:confining pressure3 (mpa)peak axial stress1 (mpa)angle between cleavage and1 o2.05.010.015.020.062.062.580.095.0104.04032373927in each test ,failure occurred by shear along the cleavage. determine the shear strength criterion for cleavage plans.6 in a further series of tests on the slate for which the data of problem 5 were obtained, it was found that, when failure occurred in directions other than along the cleavage, the peak strength of rock material was given by 1=150+2.83where 1 and 3 are in mpa.construct a graph showing the expected variation of peak axial stress at a confining pressure of 10 mpa, as the angle between the cleavage and the specimen axis varies from 0oto90o.7 the following results were obtained in a series of direct shear tests carried out on 100 mm square specimens of granite containing clean, rough, dry joints.normal stresspeak shear strengthresidual shear strengthdisplacement at peak shear strengthnormalshearn(mpa)p(mpa)r(mpa)(mm)(mm)0.250.250.150.542.000.500.500.300.672.501.001.000.600.653.202.001.551.150.453.603.002.151.700.304.004.002.600.154.20(a) determine the basic friction angle and the initial roughness angle for the joint surfaces.(b) establish a peak shear strength criterion for the joints, suitable for use in the range of normal stresses, 0-4mpa.(c) assuming linear shear stress-shear displacement relations to peak shear strength， investigate the influence of normal stress on the shear stiffness of the joints.8 a triaxial compression test is to be carried out on a specimen of granite referred to in problem 7 with the joint plane inclined at 35o to the specimen axis. a confining pressure of 3=1.5mpa and an axial stress of 1=3.3mpa are to be applied. then a joint water pressure will be introduced and gradually increased with 1 and 3 held constant. at what joint water pressure is slip on the joint expected to occur? repeat the calculation for a similar test in which 1=4.7mpa and 3=1.5mpa.9 in the plane of cross section of an excavation, a rock mass contains four sets of discontinuities mutually inclined at 45o. the shear strengths of all discontinuities are given by a linear coulomb criterion with c=100kpa and =30o.develop an isotropic strength criterion for the rock mass that approximate the strength obtained by applying jaegers single plane of weakness theory in several parts.10 a certain slate can be treated as a transversely isotropic elastic material. block samples of the slate are available from which cores may be prepared with the cleavage at chosen angles to the specimen axes. nominate a set of tests that could be used to determine the five independent elastic constants in equation 2.42 required to characterize the stress-strain behavior of the slate in uniaxial compression. what measurements should be taken in each of these tests? 5 pre-mining state of stress5.1 specification of the pre-mining state of stressthe design of an underground structure in rock differs from other types of structural design in the nature of the loads operating in the system. in conventional surface structures, the geometry of the structure and its operating duty define the loads imposed on the system. for an underground rock structure, the rock medium is subject to initial stress prior to excavation. the final, post-excavation state of stress in the structure is the resultant of the initial state of stress and stresses induced by excavation. since induced stresses are directly related to the initial stresses, it is clear that specification and determination of the pre-mining state of stress is a necessary precursor to any design analysis.the method of specifying the in situ state of stress at a point in a rock mass, relative to a set of reference axes, is demonstrated in figure 5.1. a convenient set of cartesian global reference axes is established by orienting the x axis towards mine north, y towards mine east, and z vertically downwards. the ambient stress components expressed relative to these axes are denoted pxx , pyy, p zz, p xy, pyz, p zx. using the methods established in chapter 2, it is possible to determine, from these components, the magnitudes of the field principal stress pi(i=1,2,3), and the respective vectors of direction cosines (xi, yi, zi) for the three principal axes. the corresponding direction angles yield a dip angle, i, and a bearing, or dip azimuth,i, for each principal axis. the specification of the pre-mining state of stress is completed by defining the ratio of the principal stresses in the form p1:p2:p3=1.0:q:r where both q and r are less than unity.the assumption made in this discussion is that it is possible to determine the in situ state of stress in a way which yields representative magnitudes of the components of the field stress tensor throughout a problem domain. the state of stress in the rock mass is inferred to be spatially quite variable, due to the presence of structural features such as faults or local variation in rock material properties. spatial variation in the field stress tensor may be sometimes observed as an apparent violation of the equation of equilibrium for the global z (vertical) direction. since the ground surface is always traction-free, simple statics requires that the vertical normal stress component at a sub-surface point be given bypzz=z (5.1) where is the rock unit weight, and z is the depth below ground surface.failure to satisfy this equilibrium condition (equation5.1)in any field determination of the pre-mining state of stress may be a valid indication of heterogeneity of the stress field. for example, the vertical normal stress component might be expected to be less than the value calculated from equation 5.1, for observations made in the axial plane of an anticlinal fold.a common but unjustified assumption in the estimation of the in situ state of stress is a condition of uniaxial strain (complete lateral restraint)during development of gravitational loading of a formation by superincumbent rock. for elastic rock mass behavior, horizontal normal stress components are then given by pxx=pyy=1-pzz (5.2)where is poissons ratio for the rock mass.if it is also assumed that the shear stress components p xy, pyz, p zx are zero, the normal stresses defined by equations 5.1and 5.2 are principal stresses. reports and summaries of field observations (hooker et al.,1972;brown and hoek,1978) indicate that for depths of stress determinations of mining engineering interest, equation 5.2 is rarely satisfied, and the vertical direction is rarely a principal stress direction. these conditions arise from the complex load path and geological history to which an element of rock is typically subjected in reaching its current equilibrium state during and following orebody formation. 译文 问题 1在3 = 2.0mpa的条件下，石灰石的初始弹性行为包括计算切线模量和泊松比可由图4.18所给出的数据显示出来。 2多孔砂岩的单轴抗压强度c=75mpa 。由一系列的三轴压缩试验结果绘制出的剪应力正常应力轴显示的库仑强度峰值线性强度包络图有一个45o的倾斜。 确定套嵌标本遭受的围压3=10mpa轴向强度应力峰值。如果套嵌在试验过程中被刺破，孔隙水压力已建立起一个平衡的围压值，那么轴向应力峰值又会怎样？ 3 ( a )建立一个大理岩近似峰值强度包络图如图4.19所示。 3 ( b )通过采取何种方式可以观测到试样的应力应变行为由不同的试验进行了常规试验机上得出的线性刚度为2.0gnm-1 ？假定所有标本，直径为50mm长100毫米。 岩石强度和应变4一系列完整的石英岩试样的实验室试验给出了以下平均强度峰值。应力的单位是兆帕，并且压缩性为刚性。 三轴压缩2=3100100135130160150200180298248435335双轴拉伸/压缩123000-13-13.521850-13225100022815002102100制定一个石英岩的峰值强度标准用于地下洞室的开挖设计。经验表明，石英岩的原位单轴抗压强度值是实验室所测值的一半。 5一系列板岩试样的三轴压缩试验结果如下： 围压3 (mpa)轴向应力峰值1 (mpa)解理和1的角度(o)2.05.010.015.020.062.062.580.095.0104.04032373927在每一个试样中，试样沿着解理面发生剪切破坏。进而确定解理平面图的抗剪强度标准。6在问题5所得数据的基础上，对板岩做了一系列进一步的实验，人们发现，当破坏方向不是沿着解理时，岩石材料的峰值强度由公式 1=150+2.83 计算得到。其中1和3的单位为mpa。构建一个图表显示了轴向应力峰值在围压为10兆帕时的预期变化，因为解理和试样轴向之间的夹角从0o到90o 变化。7以下结果是在一系列100毫米见方的含有新鲜，粗糙，隐形裂隙交织的花岗岩试样上进行直接剪切试验得到的。正应力峰值抗剪强度残余抗剪强度位移峰值抗剪强度法向切向n(mpa)p(mpa)r(mpa)(mm)(mm)0.250.250.150.542.000.500.500.300.672.501.001.000.600.653.202.001.551.150.453.603.002.151.700.304.004.002.600.154.20(a)确定交接面处的基本摩擦角和初始粗糙度。 (b)建立一个节理峰值抗剪强度标准，适用于正应力变化范围为0-4mpa。 (c)假设线性剪切应力剪切位移和峰值抗剪强度有关，研究正应力对节理剪切刚度的影响。 8三轴压缩试验是在问题7所提到的花岗岩试样上进行的，这个试样的节理面向轴线以35o倾斜。施加3=1.5mpa的围压和1=3.3mpa轴向应力。这时节理水压力将会随着1和3的保持不变而逐渐增大。当节理水压力为多大时节理将发生预期滑动平移？重复计算在1 = 4.7mpa和3 =1.5mpa时的类似试验。 9在交叉的开挖横断面，岩体包含四处相互倾斜45o的不连续面。所有不连续面的抗剪强度均由c= 100kpa，=30o时的线性库伦准则得出。 制定一套岩体各向同性强度准则，这与耶格尔的单一薄弱面理论的很多方面都相似。10某板岩可以视为横断的各向同性弹性材料。块状板岩试样可取自节理与轴向成选定角度的试样上。提出一系列试验，可用于确定公式2.42中五个独立的弹性常数，