交通工程专业英语翻译The_Evolution_of_Transport.doc

The Evolution of Transport 交通运输业的发展The evolution of transport has been closely linked to the development of humankind throughout the earths history交通运输的发展一直与的人类发展的整个地球的历史密切联系在一起。Transports early function was to meet the basic need of hauling food supplies and building materials运输的早期功能是为了满足食物供给和搬运建筑材料的基本需求。But with the formation of tribes，then peoples，and finally nations，the societal and economic functions of transport became more and more complex. 但是随着部落的产生甚至最后国家的形成，运输在社会和经济起到的功能越来越复杂。At first there was mobility required for individuals，clans，households，and animals to protect them against，and to escape from，the dangers of natural disasters and tribal aggressions，and in the search for the best places to settle起初有需要调动个人，家族，家庭和动物以保护他们来反抗并逃避自然灾害和部族侵略的危险，从而寻找最好的地方定居。As tribal groups formed and gradually established their geographical identity，transport was increasingly needed to open up regions for development，to provide access to natural resources，to promote intercommunal trade，and to mobilize territorial defense随着种族部落的形成和地理界线的逐步确定，开发新区域、开采新资源、发展社区间的贸易以及捍卫领地，这些都日益需要交通的发展。When the first nations came into being，transport played a major role in establishing national integrity当第一个国家应运而生,在建立全国的完整性方面,交通运输扮演着重要角色。After basic societal needs had generally been attended to，local communities could increasingly devote their efforts to enhancing their economic，cultural，and technological development through trade links with other peoples and regions基本的社会需求一般都得到满足后，当地社区可以越来越多地贡献自己的努力，用来加强他们的经济，文化和科技发展，通过贸易来联系其他国家的人民。Again，transport provided the mobility required for such intertribal, international，and finally intercontinental cultural exchange and trade而且交通提供了诸如部落间、国际间乃至于洲际间便利的贸易和文化交流。During all of this gradual development toward an organized human society，represented today through the international family of nations，transport as physical process of moving people and goods，thus promoting such development，continuously underwent technological and organizational changes在向有组织的人类社会的演变过程中，这种组织在今天是通过由各国组成的国际化大家庭表现出来的，交通作为人与货物移动的物理过程，也促进了这种发展，不断地经历着技术与组织方面的改变。Such changes were induced by several factors and circumstances这些变化是由多种因素和情况引起的。In fact，todays transport in its various forms and organizational arrangements remains highly subject to changes in response to societal requirements and preferences事实上,今天的运输在它的各种形态和组织安排上仍然高度受到在社会需求和偏好回应的改变所支配。Clearly，the first and foremost criterion to be satisfied by transport was efficiency显然,首先也是最重要的标准是运输效率。For centuries，and particularly during the takeoff stages of local economics，society required reliable，fast，and low cost transport几个世纪以来，特别是在地方经济起飞阶段，社会需要可靠、快速和低成本的运输。The search for appropriate technologies was relatively unconstrained为寻找相对不受限制的合适技术。There were times in human history when the demand for reliable and fast transport was especially pronounced，and quick solutions were required for national self-defense. 在人类历史上，可靠和快速运输的需求尤其明显，这是提供国家自卫所需的快速解决办法。During such periods of local and international conflict, human ingenuity devised new transport technologies which often proved to be the decisive element for survival, and sometimes victory. 在当地和国际冲突的时期内，人类的聪明才智制定出新的运输技术，往往被证明是为逃生有时也为胜利的决定性因素。 Subsequently refined and developed, such new technologies made it possible to better meet increasing transport demand, thus improving both economic progress and human welfare.随后的完善和发展，这种新技术使人们有可能更好地满足日益增加的运输需求，从而改善经济的发展和人类福利。The need for better strategic mobility induced efforts to improve sea and land transport. 为更好的战略机动诱导努力提高海上和陆地运输的需要。 This resulted in bigger and faster ships and more reliable and sturdy land vehicles. 这导致了更大、更快的船和更可靠、坚固的陆地车辆。Eventually, self-propulsion was introduced, exemplified by steamboats, the railways, and then the automobile. 最后，自我推进介绍，使得汽船、铁路，然后是汽车均得以例证。 Research and development in the transport field finally became an organized undertaking with specific goals and objectives. 运输领域的研究和发展终于成为一个具体的目标和有组织目标的承诺。As the result of the consequent concentration of talent and expertise, more and more sophisticated transport technologies evolved, such as the aircraft and, most recently, rocket propulsion.随之而来的是人才和专业知识的集中，越来越复杂的运输技术在进化,如飞机和最新的火箭推进器。The gradual evolution of increasingly sophisticated means of transport is manifested by todays transport systems, which include air, surface, and water transport. 日益复杂的运输手段逐渐发展成今天的运输系统，其中包括空中、路面和水上运输。Special industry needs have led to the development of transport modes that have rather limited applications, such as pipelines, cables, and belts. 特殊行业的需求，引起了相当有限的应用的运输模式的发展，如管道，电缆和传送带。Within current societal needs and preferences, as well as the economic requirements of cost effectiveness, the various existing transport modes generally fulfill rather specific functions.因为当前社会的需求和偏好，以及经济成本效益的要求，现有的各种运输方式一般都能完成特定功能。Although transports potential to meet effectively numerous societal mobility needs improved continuously, it became evident that such effectiveness had its price. 尽管运输的潜力以满足社会的流动性需要不断提高，但很明显，这种效益有其代价。A number of transport technologies implied high energy consumption and required substantial capital inputs in production and operation. 大量的交通技术意味着高能量的消耗能以及要求大量的资金投入生产和经营。As a result, several transport modes became expensive to the user. 因此，一些运输方式对使用者来说是昂贵的。This caused equity problems because charges required to cover operating costs were not affordable by all population groups, thus limiting their mobility and welfare. 这引起权益问题，因为需要支付运营成本的费用是不是所有的人口群体负担得起，从而限制其流动性和福利。Many governments chose to subsidize transport, but quickly realized that the budget implications often caused serious distortions in their national economies.许多国家的政府选择了运输补贴，但很快就意识到，预算往往对本国经济造成严重的扭曲。Pollution caused by various transport modes gradually became another serious problem as world transport in most countries and the need to cope with rising volumes of commodity flows and person travel. 各种运输方式造成的污染逐渐成为另一问题，如同世界大多数国家的运输需要应付不断上升的商品流动和人的旅行量严重的问题。In several regions of the world having high population and industry concentrations, such detrimental impacts on the environment have reached high levels. 在一些地区具有高浓度的人口和产业，这种对环境的不利影响已达到很高的水平。These effects of such damage yet are to be fully explored.这种损害引起的这些影响尚未得到充分开发。Finally, problems caused by dwindling world energy resources, particularly petroleum, have increasingly impeded transport services and operations. 最后，这些问题引起世界能源资源的日益减少，特别是石油，已越来越多地阻碍交通服务和操作。Most existing transport modes are critically dependent on petroleum derivatives for proper functioning. 大多数现有的运输方式都是以依赖石油衍生品才能正常运转。With unabated growth of demand for transport and a progressively limited supply of energy, the costs of providing transport have increased steadily. 随着运输需求量的不衰减地增长和能源供应的有限，提供运输的成本已经稳步增加。In particular, the disproportion of petroleum requirements and petroleum supply has caused serious inflationary problems to arise in many countries. 特别是，石油需求和石油供应不均衡造成了严重的通货膨胀问题出现在许多国家。Especially hard hit are countries with a partial or total dependence on an external petroleum supply, which have experienced growing deficits in their current accounts.尤其沉重地打击那些部分或是完全依赖外部石油供应并经历了他们经常账户赤字增长的国家。The transport sectors increasing inability to satisfy demand efficiently and equitably is a problem with which all nations have to cope in trying to advance economic and social progress. 运输部门的增加无法满足有效且公平的需求，是一个所有国家必须应对努力促进经济和社会进步的问题。 Energy-supply constraints, high capital and operating costs, often with excessive foreign-exchange components, and the seriousness of transport-related environmental pollution account in large part for this problem. 能源供应的限制，高额的资本和运营成本，往往与过度的外汇组件以及与运输有关的环境污染的很大一部分用于这个严重性的问题。But transport is and will continue to be an essential requirement for world development and human welfare. 但运输是并将继续是世界的发展和人类福利的基本要求。There is no other choice but to look for alternatives to present transport systems or to modify the technical and operational characteristics of related modes so that energy consumption and costs wil1 be reduced and environmental impacts can be kept at a minimum. 没有别的办法，只能寻求新的交通替代手段或改变相关模式的技术与运行特点，才可以减少能源消耗和造价，对环境的影响也可以保持到最低程度。Obviously, the development of transport demand will have to be controlled.显然，交通需求的发展将不得不被控制。交通工程专业英语 翻译 Unit 17 Highway Capacity道路通行能力Capacity and levels of services服务水平和通行能力A principal objective of capacity analysis is the estimation of the maximum number of people or vehicles that can be accommodated by a given facility in reasonable safety within a specified time period. 道路通行能力分析的主要目标就是对在某个时间段内，在保证合理安全的条件下道路由已给定的道路设施所能容纳的行人或汽车的最大流量的评价。 However, because facilities generally operate poorly at or near capacity, they are rarely planned to operate in this range. 然而，由于通常情况下道路设施很难达到或接近通行能力，所以在此领域，很少有人对其做评估。Accordingly, capacity analysis also provides a means of estimating the maximum amount of traffic that can be accommodated by a facility while maintaining prescribed operational qualities. 因此，通行能力分析也提供了一种用于估算某种设施在保证规定的运行质量条件下所能适应的最大交通量的方法。Capacity analysis is, therefore, a set of procedures for estimating the traffic-carrying ability of facilities over a range of defined operational conditions. 因此，通行能力分析就是一套为估计在特定的运行状况范围内道路设施的交通承载能力的程序。 It provides tools for the analysis of existing facilities and for the planning and design of improved or future facilities. 它为现有设施的分析，改进设施或者说是未来设施的计划和设计提供了一种方法。The definition of operational criteria is accomplished by introducing the concept of levels of services. Ranges of operating conditions are defined for each type of facility and are related to amounts of traffic that can be accommodated at each level. 运行标准的定义是通过引进服务水平的概念来确定的，而运行状态范围的规定是为了确定各种类型的设施，并且它与在不同水平下所能承受的交通量有关。Ideal conditions理想条件详细的理想条件在每个章节中都给出了明确定义。对于不间断交通流设施和交叉口，下面给出了理想条件的例子。Many of the procedures in this manual provide a formula or simple tabular or graphic presentations for a set of specified standard conditions, which must be adjusted to account for any prevailing conditions not matching those specified. 在这个手册中，许多程序为整套规定的标准提供了公式或图示。这必定将会为了解释任意一种普通状况做出调整，而非去匹配那些规定好的状况。The conditions so defined are often ideal conditions. 这些定义的条件就是通常所说的理想条件。In principle, an ideal condition is one for which further improvement will not achieve any increase in capacity. 原则上，理想条件是指无论怎样改善也不能提高设施通行能力的条件。 Ideal conditions assume good weather, good pavement conditions, users familiar with the facility, and no incidents impeding traffic flow. 理想条件假定天气良好，路况良好，道路使用者能熟练使用道路设施并且没有交通事故妨碍交通流。Specific ideal conditions are identified in each chapter. 详细的理想条件在每个章节中都给出了明确定义。 Examples of ideal conditions are given below for uninterrupted flow facilities and for intersection approaches. 对于不间断交通流设施和交叉口，下面给出了理想条件的例子。Ideal conditions for uninterrupted flow facilities include the following: lane widths of12ft; clearance of 6ft between the edge of the travel lanes and the nearest obstructions or objects at the roadside and in the median; design speed of 70mph for multilane highways, 60mph for two-lane highways; only passenger cars in the traffic stream; level terrain. 非间断流设施的理想条件包括：车道宽度12英尺，路边或中央分隔带上障碍物距行车道边缘宽6英尺，多车道公路设计时速70英里，双车道公路设计时速60英里，交通流中全部为小客车，平原地形。Ideal conditions for intersection approaches include the following: lane widths 12ft; level grade; no curb parking on the intersection approaches; only passenger cars in the traffic stream and no local transit buses stopping in the travel lanes; all vehicles traveling straight through the intersection; intersection located in a non-central business district area; no pedestrians; at signalized intersection approaches, green signal available at all times. 交叉路口理想条件包括：车道宽度12英尺，交叉口平顺，交叉口内无路旁停车，交通流中只有小客车，没有本地的公共汽车停在线路上；所有车辆直接通过交叉口；交叉口位于非中心商务区；无行人影响；对于有交通信号管制的交叉路口，任意时刻均为绿灯。In most capacity analyses, prevailing conditions are not ideal, and computations of capacity,service flow rate, or level of service must include predictive adjustments to reflect this absence of ideal conditions. 在多数的通行能力分析中，普通条件都不是理想的，通行能力、服务流率或者服务水平的计算必须进行预测调整以反映不能达到理想条件。 Prevailing conditions are generally categorized as roadway, traffic, or control conditions. 一般状况通常情况下分为道路状况，交通状况以及控制状况。Vehicle control and technology represent conditions that change in the long term. 车辆控制和技术代表着长时间改变的状况。Roadway conditions道路状况Roadway factors include geometric conditions and design elements. 道路条件包括几何条件和设计要素。 In some cases, these factors influence the capacity of a road, whereas in others, the factors may affect a measure of effectiveness, such as speed, while not affecting the capacity or maximum flow rate that can be carried by the facility. 许多情况下，这些因素会影响道路通行能力，虽然这些因素不会影响可以用设备测得的通行能力和最大交通流率，但是在其他方面，这些因素可能会影响测量效果，比如说速度，虽然这些因素不会影响可以用设备测得的通行能力和最大交通流率。Roadway factors include the following: 道路因素包括如下几个方面：The type of facility and its development. 1 设备的类型以及它的开发情况；Lane widths. 2 道路宽度Shoulder widths and lateral clearances. 3 路肩宽度和横向余宽Design speed.4 设计速度Horizontal and vertical alignments. 5 平面线性和纵断面线性Availability of queuing space at intersections6 交叉口排队距离的有效性The type of facility is critical. 设备类型起着决定性的作用。The existence of uninterrupted flow, the presence of medians, and other major facility type factors significantly affect flow characteristics and capacity. 不间断流和中央分隔带的存在，以及其他主要设施类型因素严重影响着交通流特性和通行能力。 The development environment has also been found to affect the performance of two-lane roadways, multilane highways, and signalized intersections.人们发现，环境的改善同样影响着双车道、多车道道路和有信号控制交叉口的性能。Lane and shoulder widths can have a significant impact on traffic flow. 车道和路肩的宽度对交通流有重要影响。Narrow lanes cause vehicles to travel closer to each other laterally than most drivers would prefer. .窄的车道会使车辆以比普通超车更近的距离超越其他车辆。Motorists compensate by slowing down or observing larger longitudinal spacing for a given speed, which effectively reduces capacity, service flow rates, or both.司机会通过降低车速或者不改变车速而增加纵向间距来补偿窄车道的不足，然而，这种做法将会明显的降低通行能力或服务流率，甚至两个都降低。Narrow shoulders and lateral obstructions have two important impacts. 窄路肩和侧向障碍物有着两个重要的影响。 Many drivers will steer away from roadside or median objects they perceive to pose a hazard. 许多司机会因为觉得危险而远离路边和中央分隔带。 This action brings them laterally closer to vehicles in adjacent lanes and causes the same reactions as those exhibited in narrow lanes.这些行为会使他们离相邻车道的车辆横向距离更近并且使他们表现出与在窄车道上相同的反应。Restricted design speeds affect operations and level of services; drivers are forced to travel at somewhat reduced speeds and to be more vigilant in reacting to the harsher horizontal and vertical alignments resulting from a reduced design speed. 限制设计速度将会影响道路运行和服务水平；司机将不得不以较低车速行驶并对因降低车速而导致的不合理的平纵线形变得更为警惕。 In extreme eases, the capacity of multilane facilities has been found to be affected by low design speeds.人们发现，在极端情况下，较低的设计车速会影响多车道设施的通行能力。The horizontal and vertical alignment of a highway depends greatly on the design speed used and the topography through which the roadway must be constructed. 高速公路的平、纵很大程度上取决于已有的设计速度和原始地形。Procedures for uninterrupted flow facilities categorize the general terrain of a highway as follows:规划不间断流量的一般高速公路的地形如下:(1) Level terrain平原地形Any combination of grades and horizontal and vertical alignment that allows heavy vehicles to maintain approximately the same speed as passenger cars; this terrain generally includes short grades of no more than I to 2 percent. 允许重型车辆与客车保持大约相同的速度和平、纵线性的任何组合,这种地形等级一般不会超过1-2%。(2) Rolling terrain丘陵地形Any combination of grades and horizontal or vertical alignment that causes drivers of heavy vehicles to reduce speeds to substantially bellow those of passenger cars, but dose not require operation at crawl speeds for any significant length of time. 使重型车辆的司机大幅减速低于那些客车和平、纵线性的任何组合,但不需要以爬行速度运行太长时间。(3)Mountainous terrain 山地地形Any combination of grades and horizontal and vertical alignment that causes drivers of heavy vehicles to operate at crawl speeds for significant distances or at frequent intervals. 是重型车辆在相当长的距离内或频繁的以爬坡速度行驶的坡度和平纵线型的任何组合。Crawl speed is the maximum sustained speed that heavy vehicles can maintain on an extended upgrade of a given percent. 爬坡速度是重型车辆在一定比例的延长的爬坡段上的最大行驶速度。These definitions are general and depend on the particular mix of heavy vehicles in the traffic stream. In general, as terrain becomes more severe, capacity and service flow rates are reduced. 这些定义一般是取决于交通流上的特殊的混合的重型车辆，一般来说，地形变的越加复杂严峻，通行能力和交通流速就会减小。This impact is significant for two-lane rural highways, where the seventy of terrain not only affects the operating capabilities of individual vehicles in the traffic stream, but also restricts the opportunities to pass slow-moving vehicles in the traffic stream.对于双向行驶的地形严峻的路段来说这种影响是严重的，不仅影响着交通流中个人车辆的操作能力，还制约着交通流中缓慢车流的通行机会。In addition to the general impacts of terrain, isolated upgrades of significant length may have a substantial effect on operations. 除了地形的一般影响，相当长度的上坡地段对操作也有一个明显的影响。Heavy vehicles slow significantly on such upgrades, creating operational difficulties in the traffic stream and inefficient use of the roadway. 重型车辆爬坡缓慢带来了交通流中的操作困难和道路利用效率的降低。Grades also may have a major impact on the operation of intersection approaches; vehicles must overcome both the grade and the inertia of starting from a stopped position at the same time.坡度对靠近交叉口的操作影响是重大的，车辆同一时间在停车点必须克服坡度和惯性两个困难。交通工程专业英语 翻译 Unit 16Four-Step Planning Procedure四阶段规划法Urban transportation planning calls for more than just providing for the safe and efficient movement of people and goods. It involves the planning of transportation facilities or operations responsive to the goals of the community being served. 城市运输规划要求的不仅仅只是为人和物品安全高效的流动提供条件，它还包括运输设施的计划和对被服务的公众反馈所起的效应。Identifying goals and seeing that plans are responsive to them can be difficult. 识别目标和理解人们反馈给他们的方案可能是困难的。One way to bridge gaps between community viewpoints and the planners technical processes is to set up an interlocking set of guiders that proceed from the general to the particular. 一种将公众观点和规划者的技术过程相衔接的办法是建立一套相互关联