资源描述
Unit 13 第十三单元Survey测量教学目标了解测量的内容、方法、范围和原理了解常用的测量类型熟悉各种测量方法和类型的词汇熟悉科技类文献的常用句型熟悉map、chart、plot、construction、draw的含义；so far、heretofore、by far的含义；have to do with、be referred to、be related to的含义；compatible with、pertain to 、application to 的含义；layout、staking out 的含义；construction的不同含义。Surveying has to do with（与.有关）the determination of the relative spatial location（相对空间位置）of points on or near the surface of the earth. It is the art（技术）of measuring horizontal and vertical distance between objects, of measuring angles between lines, of determining the direction of lines, and of establishing points by predetermined angular and linear measurements（角测量法和线性测量法）.测量是关于确定地球表面上或接近地球表面的点的相对空间位置。它是测量物体之间水平与垂直距离、测量线条之间夹角、确定线条方向以及通过预先确定角测量法和线性测量法来建立点的技术。Accompanying the actual measurement（度量）of survey are mathematical calculations. Distance, angles, directions, locations, elevations, areas, and volumes are thus determined from data of survey. Also, much of the information of the survey is portrayed graphically（图示描述）by the construction of maps, profiles（纵剖面图）, cross sections（横剖面图）, and diagrams(图表）.数学计算伴随着测量中的实际量度。根据测量数据就可确定距离、角度、方向、位置、标高、面积以及体积。而且，测量中的很多信息是通过绘制地图、纵横剖面图和图表，以图示形式被描述。The equipment available and methods applicable for measurement and calculation have changed tremendously in the past decade. Aerial photogrammetry（航空摄影测量）, satellite observation, remote sensing, inertial surveying（惯性测量）, and electronic distance measurement（电子测距）laser techniques are examples of modern systems（现代方法）utilized to collect data usable in the surveying process. The relatively easy access to（利用）electronic computers of all size（各种容量）facilitates the rigorous（精确的）processing and storage（处理和储存）of large volumes of data.对测量和计算，可利用的设备和可应用的方法在过去十年中已经发生了惊人的变化。航空摄影测量、人造卫星观测、遥感、惯性测量以及电子测距激光技术是现代方法中的例子，被用来收集测量过程中可使用的数据。较容易地利用各种容量的电子计算机有助于精确地处理和储存大量的数据。With the development of these modern data acquisitions（收集）and processing systems, the duties of the surveyor have expanded beyond（超出）the traditional tasks of the field（现场）work of taking measurements and the office work of computing and drawing. Surveying is required not only for conventional construction engineering projects（项目）, mapping, and property（地籍）surveys, but is also used increasingly by other physical sciences, such as geology（地质学）and geophysics（地球物理学）; biology, including agriculture, forestry, grasslands（草原）, and wildlife（野生动植物）; hydrology（水文地理学）and oceanography（海洋学）; and geography, including human and cultural resources（人文资源）.随着现代数据收集和处理系统的发展，测量员的职责已经超出了传统的现场进行测量和室内进行计算和制图的任务。不仅一般的建筑工程项目、绘制地图、地籍测量需要测量，而且也越来越多地用于其他的自然科学，如地质学和地球物理学；生物学，包括农业、林业、草原和野生动植物；水文地理学和海洋学；以及地理学，包括人文资源。The tasks in these physical science operations（活动）need to be redefined to include design of the surveying procedure（程序）and selection of equipment appropriate for the project; acquisition of data in the field or by way of remote station; reduction（整理）or analysis of data in the office or in the filed; storage of data in a form compatible with（适合于）feature retrieval（特征检索）; preparation（整理）of maps or other displays in the graphical（绘图）(including photographic摄影) or numerical form needed for the purpose of survey; and setting of monument（界标）and boundaries in the field as well as control for construction layout（施工放样）. Performance of these tasks requires a familiarity with the uses of surveying, knowledge of fundamentals of the surveying process（方法）, and knowledge of various means by which data can be prepared for presentation.这些自然科学活动的任务需要重新定义，包括设计测量程序和选择适合该项目的设备；在现场或通过远距离的测站收集数据；在室内或现场整理或分析数据；以适合于特征检索的形式储存数据；以测量所需的绘图（包括摄影）或数字形式整理地图或其他显示；在现场设置界标和边界并控制施工放样。这些任务的实施需要熟悉测量的使用、测量方法的基本原理的知识以及数据准备表达的不同方法的知识。The earliest surveys known were for the purpose of establishing（确定）the boundaries of land, and such surveys are still important work of many surveyors.最早了解的测量是用来确定土地的边界，这样的测量仍然是很多测量员的重要工作。Every construction project of any magnitude（规模）is based to some degree upon measurements taken during the progress（发展）of a survey and is constructed about lines and points established by the surveyor. Aside from land surveys, practically all surveys of a private nature（私营性质）and most of those conducted by public agencies（公共机构）are of assistance in the conception（规划）, design, and execution （施工）of engineering works.在测量的发展过程中，任意规模的每个建筑项目在某种程度上都是根据所采用的测量方法，然后绘制由测量员确定的线和点。除了土地测量外，实际上所有私营性质的测量和大多数由公共机构经营的测量都对工程的规划、设计和施工有帮助。For many years the government, and in some instances（在某些情况下）the individual states, have conducted surveys over large areas for a variety of purposes. The principal work so far（迄今为止）accomplished consists of the fixing（确定）of national and state boundaries; the charting（绘制）of coastlines（海岸线） and navigable（适于航行的）streams and lakes; the precise location（定位）of definite reference points（固定基准点）throughout the country; the collection of valuable facts（论据）concerning the earths magnetism（磁力） at widely scattered stations; establishment（建立）and observation of a greater network of gravity station（重力站）throughout the world; the establishment and operation（运转）of tidal and water level （潮位和水位）station; the extension（扩充）hydrographic（与水文地理学有关）and oceanographic（与海洋学有关）charting and mapping（绘制）into the approximately three-fourths of the world which is essentially（本来）unmapped; and the extension of topographic（地形的）mapping of the land（陆地）surfaces of the earth. 很多年来，政府以及在某些情况下各个州已经对大量的各种用途的区域进行了测量。迄今为止，已经完成的主要工作包括确定了国家和州的边界线；绘出了海岸线和适于航行的河流和湖泊；精确定位了遍及全国的固定基准点；收集了遍布各个分散测站的关于地球磁力的有价值的论据；建立和观测了遍布世界的较大网络的重力站；建立和运转了潮位和水位站；扩充绘制了本来未绘制的约3/4的世界范围内与水文地理学和海洋学有关的图表和地图；扩充绘制了地球表面陆地的地形图。Observations of a worldwide net of satellite triangulation stations（三角测量卫星观测站） were made during the decade 1964-1974. Results of the computations have been completed by 1985. They allow（有助于） determination of the shape of the earth from one to two orders of magnitude（数量级）better than has heretofore（迄今为止）been known. Consequently, surveys of global extent（全球范围）have been performed and will become common in the future.在1964到1974年的十年间建立了全世界网络的三角测量的卫星观测站。到1985年已经完成了计算结果。它们有助于更精确地确定地球的形状，其精度要比迄今为止所知的高出一到两个数量级。因此，已经进行了全球范围的测量，这在将来成为平常事。Thus surveys are divided into three classes: (a) those for the primary purpose of establishing the boundaries of land, (b) those providing information necessary for the construction of public or private works, and (c) those of large extent and high precision conducted by the government and to some extent by the states. There is no hard and fast line of demarcation（严格的界线）between surveys of one class and those of another（不同类型） regarding the methods employed, results obtained, or the use of the data of the survey.因此，测量被分为三类：（a）主要用于确定土地边界的测量；（b）为公共或私人工程的建造提供必要信息的测量；（c）由政府以及在某种程度上由州进行的大范围和高精度的测量。不同类型的测量在采用的方法、取得的成果或测量数据的使用方面没有严格的界线。Different types of surveying undertake（承担）the tasks of three classes. Geodetic surveying（大地测量） is employed in the third class, which takes into account the true shape of the earth. Surveys making use of the principles of geodesy（测地学）are of high precision and generally extend（遍布）over large areas. Where the area involved is not great, as for a state, the required precision may be obtained by assuming that the earth is a perfect sphere（球体）. Where the area is large, as for a country, the true spheroidal（椭球体）shape of the earth is considered. Surveys of the latter character have been conducted primarily through the agencies of governments. In the United States such surveys have been conducted principally by the U.S. National Geodetic Survey. Geodetic surveys have also been conducted by the Great Lake Survey, the Mississippi River Commission, several boundary commissions, and others.不同类型的测量承担着这三类任务。大地测量被用于第三类的任务，它考虑了地球的实际形状。利用测地学原理的测量具有很高的精度，且通常遍布很大的范围。对包含的范围不大如一个州时，则可通过假定地球完全是个球体可以得到所需的精度。对范围较大如一个国家时，则要考虑地球实际的椭球体形状。对后者特征的测量主要通过政府机构进行。在美国这样的测量主要由美国国家大地测量局进行。大地测量也已由大湖勘测局、密西西比河委员会、一些边界线委员会以及其他机构进行。Though relatively few engineers and surveyors are employed full time in geodetic work（测量工作）, the data of the various geodetic surveys are of great importance in that they furnish（提供）precise points of reference to which the multitude of（大量）surveys of lower precision may be tied（连接）. For each state, a system of plane coordinates（平面坐标系统）has been devised（建立）, to which all points in the state can be referred without an error of more than one part in 10 000 in distance or direction arising from the difference （差异）between the reference surface and the actual mean surface of the earth.尽管较少的工程师和测量员专职从事测量工作，但是各种大地测量的数据很重要，它们提供了精确的基准点，大量较低精度的测量可与其联测。每个州都已建立了一个平面坐标系统，州内各点均可以参考这一坐标系统，基准面与实际的地球平均面之差所引起的距离或方位的误差不会大于1/10000。That type of surveying in which the mean surface of the earth is considered as a plane, or in which its spheroidal shape is neglected, is generally defined as plane surveying. With regard to horizontal distances and directions, a level line（水平线）is considered as mathematically straight, the direction of the plumb line（铅垂线）is considered to be same at all points within the limits of the survey, and angles are considered to be plane angles. By far（到目前为止）the greater number of all surveys are of（属于）this type. In general the surveys necessary for the works of human beings are plane survey. The shape of the earth must be taken into consideration only in surveys of precision covering（涉及）large areas.认为地球的平均面是一个平面或忽略椭球体形状的测量通常定义为平面测量。关于水平距离和方向，水平线在数学意义上被认为是直的，铅垂线的方向在测量限制范围内的所有点上被认为是相同的，而角度被认为是平面角。到目前为止，大多数的测量都属于这种类型。通常对人类工程必需的测量是平面测量。地球的形状只在涉及大范围的精确测量时才被考虑。The operation（工作）of determining elevation is usually considered as a division（一部分）of plane surveying. Elevations are referred to（与.有关）a spheroidal surface, a tangent at any point in the surface being normal to（垂直于）the plumb line at that point. The curved surface of reference, usually mean sea level（平均海平面）, is called a “datum” or curiously and incorrectly, a “datum plane”. The procedure ordinarily used in determining elevations automatically takes into account the curvature（曲率）of the earth, and elevation referred to the curved surface of reference are secured（获得）without extra effort on the part of the surveyor. In this procedure, the curvature of the earths surface can not be neglected even for very rough（粗略的）values of elevations.确定标高的工作通常被认为是平面测量的一部分。标高和椭球体表面有关，该表面上任意一点的切线垂直于该点的铅垂线。通常是平均海平面的参考曲面被称为“基准面”，或奇怪地、不恰当地称为“基准平面”。通常用来确定标高的方法自动考虑了地球的曲率，而关于参考曲面的标高，测量员没有额外的费力就可获得。在该方法中，地球表面的曲率不能被忽略，即使对非常粗略的标高值。Here a brief description of the various types of surveys will be given. Most of them employ plane rather than geodetic techniques.这里将给出一个关于不同测量类型的简短描述。它们中多数采用平面技术而不是大地测量技术。Land surveys are the oldest type of survey and have been performed since earliest recorded history. They are plane surveys made for locating property lines（地籍线）, subdividing land into smaller parts（分割土地）, determining land areas and any other information involving the transfer of land from one owner to another（土地产权转移）. These surveys are also called property surveys, boundary surveys, or cadastral surveys.土地测量是最老的测量类型，自从最早有历史记载以来就已有之。它们属于平面测量方法，用以定位地籍线、分割土地、确定土地面积以及其他包括土地产权转移在内的信息。这些测量也称为地籍测量、边界测量或地产测量。Topographic surveys（地形测量）are made for locating objects and measuring the relief（地貌）, roughness（粗糙度）, or three-dimensional variations of the earths surface. Detailed information is obtained pertaining to（关于）elevations as well as to the locations of man-made and natural features（人工和自然地物） (buildings, roads, streams, and so on) and the entire information is plotted on maps (called topographic maps).地形测量用以定位物体以及测出地球表面的地貌、粗糙度或三向空间的变化。在得到了关于人工和自然地物（建筑物、道路、河流等）的标高和位置的详细信息后，将全部的信息绘在地图上（称为地形图）。Route surveys（路线测量）involve the determination of the relief and the location of natural and artificial objects along a proposed（拟定的）route for a highway, railroad, canal, power line（输电线）, or other utility（应用）. They may further involve the location or staking out（放样）of the facility and the calculation of earthwork quantities（土方工程量）.路线测量包括确定自然和人工的物体如公路、铁路、运河、输电线或其他应用沿着拟定路线的地貌和位置。它们可进一步包括设施的定位或放样，并计算土方工程量。City survey are made within a given municipality for the purpose of laying out（定位）streets, planning（布置）sewer systems（排水系统）, preparing maps, and so on. When the term is used, it usually brings to mind（使人想起）topographic surveys in or near a city for the purpose of planning urban expansions or improvements.城市测量是在一个特定的城市范围内用以定位街道、布置排水系统以及制作地图等。当采用该术语时，它通常使人想起在一个城市中或城市边进行的地形测量，用以规划城市的扩张和改进。Construction surveys are made for purposes of locating structures and providing required elevation points during their construction. They are needed to control（指导）every type of construction project.建筑测量用以确定建筑的位置，并在施工期间提供所需的标高点。它们被需要用来指导每种建筑工程。Hydrographic surveys（水文测量）pertain to（适合）lakes, streams, and other bodies of water（水域）. Shore lines（海岸线）are charted, shapes of areas beneath water surface are determined, water flow（水流量） of streams is estimated, and other information needed relative to（相对于）navigation, flood control（防洪）, development of water resources, and so on, is obtained. These surveys are usually made by a governmental agency. When hydrographic and topographic surveying are combined the resulting surveys are sometimes called cartographic survey（地图制图测量）.水文测量适合于湖泊、河流以及其他水域。绘出海岸线、确定水面下区域的形状、估计河流的水流量以及得到其他相对于航海、防洪、水资源发展等所需要的信息。这些测量通常由政府机构进行。当水文测量与地形测量结合起来形成的测量有时称为地图制图测量。 Marine surveys（海洋测量）are related to hydrographic surveys but they are thought to cover a broader area. They include the surveying necessary for offshore platforms（近海平台）, the science of navigation, theory of tides（潮汐学说）as well as the preparation of hydrographic maps and charts（海图）. 海洋测量与水文测量有关，但被认为包含更广泛的区域。它们包括近海平台、航海科学、潮汐学说以及制作水文图和海图所必需的测量。Mine surveys（矿井测量）are made to obtain the relative positions and elevations of underground shafts（矿井）, geological formations （地质组成）, and so on and to determine quantities and establish lines and grades for work to be done.矿井测量用以获得地下矿井的相对位置和标高、地质组成等，并确定将要进行的工作的数量、路线和等级。Forestry and geological surveys（林地和地质测量）are probably much more common than the average（一般的）layman realizes（了解）. Foresters（林务员）use surveying for boundary locations, timber cruising, topography, etc. Similarly, surveying has much application in the preparation of geological maps（地质图）.林地和地质测量可能比一般的非专业人员所了解的普遍的多。林务员进行边界位置测量、森林勘测测量、地形测量等。类似的，测量在制作地质图时有很多应用。Photogrammetric surveys（摄影测量）are those in which photographs (generally aerial) are used in conjunction with（加上）limited（有限的）ground surveys (used to establish or locate certain control points visible from the air). Photogrammetry is extremely valuable because of the speed with which it can be applied, the economy, the application to（适用于）areas difficult to access（达到）, the great detail provided, etc. Its uses are becoming more extensive each year.摄影测量是利用照片（通常是空中的）加上有限的地面测量进行的测量（用以确定从空中能看见的某些控制点的位置）。摄影测量非常有价值，因为这种测量速度快、经济、适用于难以到达的地区以及提供大量的详细资料等。它的使用一年比一年广泛。In the decades to come there will undoubtedly be the other special types of surveying which will develop. Surveyors might very well（极有可能）have to establish boundaries under the ocean, in the Arctic and Antarctic, and even on the moon and other planets. Great skill and judgment by the surveying profession（测量业）will undoubtedly be required to handle these tasks.在今后的几十年里，毫无疑问会有其他特殊类型的测量将逐步发展。测量员极有可能不得不在海洋下、在北极和南极、甚至在月球和其他行星上确定边界。毫无疑问测量业将需要很多的技能和判断来处理这些任务。Unit 15 第十五单元Soil Mechanics 土力学教学目标了解土的颗粒尺寸熟悉土壤类型及其力学和物理性能的词汇熟悉科技类文献的常用句型熟悉frictional、cohesive的不同含义；drop、lower、sink、settle的不同含义。Grain size（颗粒尺寸）is the basis of soil mechanics, since it is this which decides whether a soil is frictional（有摩阻力的）or cohesive（有粘结力的）, a sand or a clay（粘土）. Starting with the largest sizes, boulders（漂石）are larger than 10 cm, cobbles（卵石）are from 5 cm to 10 cm, gravel（砾石）or ballast（碎石）is from about 5 cm to 5 mm, grit（粗砂）is from about 5 mm to 2 mm, sand is from 2 mm to 0.06 mm. All these soils are frictional, being coarse（粗糙的）and thus non-cohesive. Their stability depends on their internal friction. For the cohesive or non-frictional soils the two main internationally accepted size limits（范围）are: silt（淤泥）from 0.02 mm to 0.002 mm, and clay for all finer material. There are, of course, many silty clays（粉质粘土）and clayey silts（粘质粉土）.土力学的基础是颗粒尺寸，因为是它决定了土壤是有摩阻力的还是有粘结力的，是砂还是粘土。从最大的尺寸开始，漂石大于10cm，卵石在5cm到10 cm之间，砾石或碎石约在5cm到5mm之间，粗砂约在5mm到2mm之间，砂在2mm到0.06mm 之间。所有这些土壤都是有摩阻力的，是粗糙的，因而是没有粘结力的。它们的稳定性依赖于内摩擦力。对于有粘结力或无摩擦力的土壤，国际上能接受的两个主要的尺寸范围是：淤泥在0.01mm到0.002mm，而粘土为所有较细的材料。当然还有很多粉质粘土和粘质粉土。Every large civil engineering job starts with a soil mechanics survey（地基勘测）in its early stage. The first visit on foot（踏勘）will show whether the site might be suitable, in other words, whether money should be spent on sending soil-sampling equipment out to it. The soil samples and the laboratory results obtained from the triaxial test, shear test and so on will show at what depth the soil is likely to be strong enough to take the required load. For a masonry or steel structure, this is where soil mechanics survey will end, having rarely cost more than 2 percent of the structure cost.每一项大的土木工程任务在它的早期阶段是从地基勘测开始的。通过最初的踏勘显示该场地是否适合，换句话说，是否应该花一定的费用运送土壤取样设备至现场。土壤样本以及根据三向试验、剪切试验等所获得的实验室结果将显示在哪个深度上土壤可能足够坚固，能承受所需的荷载。对砌体或钢结构来说，其地基勘察将到此结束，所需费用很少超过结构费用的2%。Generally, the strength of a soil increases with depth. But it can happen that it becomes weaker with depth. Therefore, in choosing the foundation pressure（地基压力）and level（深度）for this sort of soil, a knowledge of soil mechanics is essential, since this will give an idea of（对.有所了解）the likely settlements.通常，土的强度随深度而增加。但会发生强度随深度变弱的情况。因此，在选择这种土的地基压力和深度时，土力学的知识是必要的，因为这将对可能的沉降有所了解。There are, however, several other causes of settlement apart from consolidation（固结）due to load. These causes are incalculable（不可计算的）and must be carefully guarded against（预防）. They include frost（霜冻）action, chemical change in the soil, underground erosion（侵蚀）by flowing water, reduction of the ground water level, nearby construction of tunnels（隧道）or vibrating machinery（机械）such as vehicles.但是，除了荷载引起的固结外，还有其他一些沉降的原因。这些原因是不可计算的，必须小心预防。它们包括霜冻作用、土壤中的化学变化、流水引起的地下侵蚀、地下水位的减少、附近隧道的施工或者振动的机械如车辆。Static load can cause elastic (temporary) or plastic （permanent） settlement, consolidation settlement being permanent. However, when plastic flow（塑性流）is mentioned in English, it generally means the failure of a soil by overload in shear. Consolidation settlement occurs mainly in clays or silts.静荷载会引起弹性（暂时的）或塑性（永久的）的沉降，其中固结沉降是永久的。但是，在英语中提到塑性流，它通常意味着超载引起土壤的剪切失效。固结沉降主要发生在粘土或淤泥中。From dynamic load alone the commonest settlements are found in sands or gravels, caused by traffic or other vibration, pile driving（打桩）or other earth shocks（冲击）. A drop（降低） in the ground water level will often cause the soil to shrink and a rise may cause expansion（膨胀）of the soil. Ground water is lowered by the drainage（排水）which can be caused by any deep excavation（深开挖）. The shrinkage which can occur with drying（干燥）is well shown by the clay underlying Mexico City, a volcanic ash. After seven weeks drying this clay shrinks to 6.4 percent of its initial volume. It is an unusual clay with the very high voids ratio（孔隙比）of 93.6 / 6.4 = 14.6.在砂或砾石中发现了仅由动荷载如交通或其他振动，打桩或其他土地冲击引起的最普通的沉降。地下水位的下降常常引起土壤的收缩，上升可能引起土壤的膨胀。由任何深开挖引起的排水可导致地下水位的降低。干燥引起的收缩可通过墨西哥城下的粘土即火山灰来很好地说明。在七个星期的干燥后，该粘土比它的初始体积收缩了6.4%。它是一种与众不同的粘土，具有很高的孔隙比，为93.6/6.4=14.6。Underground erosion is the removal of solids（固体颗粒的流失）, usually fines（细颗粒）, from the soil by the flow of underground water. The solids can be removed as solids（固态） or in solution（溶解状态）, though only a few rocks are soluble enough（充分溶解）to be removed in this way. Rock salt（岩盐）is the commonest example of a soluble rock. Potassium salts（钾盐）also are soluble.地下侵蚀是由于地下水的流动引起的固体颗粒通常是细颗粒从土壤中流失。固体颗粒能在固态或溶解状态时流失，尽管只有一些岩石能以这种形式充分溶解后流失。岩盐是可溶解的岩石中最普通的例子。钾盐也是可溶解的。The permeability（渗透性）of a soil is important for calculations of underground flow（地下潜流）, for example of oil or water to a well, or of water into a trench（排水沟）dug for a foundation, or of water through an earth dam（土坝）. Of the loose soils which can be dug with spade（铲）
展开阅读全文