1、外 文 资 料 翻 译Construction EngineeringAbstract: Construction engineering is a specialized branch of civil engineering concerned with the planning, execution, and control of construction operations for such projects as highways, buildings, dams, airports, and utility lines. Planning consists of scheduli
2、ng the work to be done and selecting the most suitable construction methods and equipment for the project. Execution requires the timely mobilization of all drawings, layouts, and materials on the job to prevent delays to the work. Control consists of analyzing progress and cost to ensure that the p
3、roject will be done on schedule and within the estimated cost.Keywords: planning, Execution, Control, Preparation of site, Earthmoving, Foundation treatment, Steel erection, Concrete construction, Asphalt paving and so on.Construction engineering is a specialized branch of civil engineering concerne
4、d with the planning, execution, and control of construction operations for such projects as highways, buildings, dams, airports, and utility lines. Planning consists of scheduling the work to be done and selecting the most suitable construction methods and equipment for the project. Execution requir
5、es the timely mobilization of all drawings, layouts, and materials on the job to prevent delays to the work. Control consists of analyzing progress and cost to ensure that the project will be done on schedule and within the estimated cost.Planning. The planning phase starts with a detailed study of
6、construction plans and specifications. From this study a list of all items of work is prepared, and related items are then grouped together for listing on a master schedule. A sequence of construction and the time to be allotted for each item is then indicated. The method of operation and the equipm
7、ent to be used for the individual work items are selected to satisfy the schedule and the character of the project at the lowest possible cost.The amount of time allotted for a certain operation and the selection of methods of operation and equipment that is readily available to the contractor. Afte
8、r the master or general construction schedule has been drawn up, subsidiary detailed schedules or forecasts are prepared form the master schedule. These include individual schedules for procurement of material, equipment, and labor, as well as forecasts of cost and income.Execution. The speedy execu
9、tion of the project requires the project requires the ready supply of all materials, equipment, and labor when needed. The construction engineer is generally responsible for initiating the purchase of most construction materials and expediting their delivery to the project. Some materials, such as s
10、tructural steel and mechanical equipment, require partial or complete fabrication by a supplier. For these fabricated materials the engineer must prepare or check all fabrication drawings for accuracy and case of assembly and often inspect the suppliers fabrication. Other construction engineering du
11、ties are the layout of the work by surveying methods, the preparation of detail drawings to clarify the design engineers drawings for the construction crews, and the inspection of the work to ensure that it complies with plans and specifications.On most large projects it is necessary to design and p
12、repare construction drawings for temporary construction facilities, such as drainage structures, access roads, office and storage buildings, formwork, and cofferdams. Other problems are the selection of electrical and mechanical equipment and the design of structural features for concrete material p
13、rocessing and mixing plants and compressed air, water, and electrical distribution systems.Control. Progress control is obtained by comparing actual performance on the work against the desired performance set up on the master or detailed schedules. Since delay on one feature of the project could eas
14、ily affect the entire job, it is often necessary to add equipment or crews to speed up the work.Cost control is obtained by comparing actual unit costs for individual work items against estimated or budgeted unit costs, which are set up at the beginning of the work. A unit cost is obtained by dividi
15、ng the total cost of an operation by the number of units in that operation.Typical units are cubic yards for excavation or concrete work and tons for structural steel. The actual unit cost for any item at any time is obtained by dividing the accumulated costs charged to that item by the accumulated
16、units of work performed.Individual work item costs are obtained by periodically distributing job costs, such as payroll and invoices to various work item accounts. Payroll and equipment rental charges are distributed with the aid of time cards prepared by crew foremen. The cards indicate the time sp
17、ent by the job crews and equipment on the different element of the work. The allocation of material costs is based on the quantity of each type of material used for each specific item.When the comparison of actual and estimated unit costs indicates an overrun; an analysis is made to pinpoint the cau
18、se. If the overrun is in equipment costs, it may be that the equipment has insufficient capacity or that it is not working properly. If the overrun is in labor costs, it may be that the crews have too many men, lack of proper supervision, or are being delayed for lack of materials or layout. In such
19、 cases time studies are invaluable in analyzing productivity.Construction operations are generally classified according to specialized fields. These include preparation of the project site, earthmoving, foundation treatment, steel erection, concrete placement, asphalt paving, and electrical and mech
20、anical installations. Procedures for each of these fields are generally, the same, even when applied to different projects, such as buildings, dams, or airports. However, the relative importance of each field is not the same in all cases.Preparation of site. This consists of the removal and clearing
21、 of all surface structures and growth from the site of the proposed structure. A bulldozer is used for small structures and trees. Larger structures must be dismantled.Earthmoving. This includes excavation and the placement of earth fill. Excavation follows preparation of the site, and is performed
22、when the existing grade must be brought down to a new elevation. Excavation generally starts with the separate stripping of the organic topsoil, which is later reused for landscaping around the new structure. This also prevents contamination of the nonorganic material which is below the topsoil and
23、which may be required for fill. Excavation may be done by any of several excavators, such as shovels, draglines, clamshells, cranes, and scrapers.Efficient excavation on land requires a dry excavation area, because many soils are unstable when wet and cannot support excavating and hauling equipment.
24、 Dewatering becomes a major operation when the excavation lies below the natural water table and intercepts the groundwater flow. When this occurs, dewatering and stabilizing of the soil may be accomplished by trenches, which conduct seepage to a sump from which the water is pumped out. Dewatering a
25、nd stabilizing of the soil may in other cases be accomplished by wellpoints and electroosmosis.Some materials, such as rock, cemented gravels, and hard clays, require blasting to loosen or fragment the material. Blast holes are drilled in the material; explosives are then placed in the blast holes a
26、nd detonated. The quantity of explosives and the blast-hole spacing are dependent upon the type and structure of the rock and the diameter and depth of the blast holes.After placement of the earth fill, it is almost always compacted to prevent subsequent settlement. Compaction is generally done with
27、 sheeps-foot, grid, pneumatic-tired, and vibratory-type rollers, which are towed by tractors over the fills it is being placed. Hand-held, gasoline-driven rammers are used for compaction close to structures where is no room for rollers to operate.Foundation treatment. When subsurface investigation r
28、eveals structural defects in the foundation area to be used for a structure, the foundation must be strengthened. Water passages, cavities, fissures, faults, and other defects are filled and strengthened by grouting. Grouting consists of injection of fluid mixtures under pressure. The fluids subsequ
29、ently solidify in the voids of the strata. Most grouting is done with cement and mixtures, but other mixture ingredients are asphalt, cement and clay, and precipitating chemicals.Steel erection. The construction of a steel structure consists of the assembly at the site of mill-rolled or shop-fabrica
30、ted steel section. The steel sections many consist of beams, columns, or small trusses which are joined together by riveting, bolting, or welding. It is more economical to assemble sections of the structure at a fabricating shop rather than in the field, but the size of preassembled units is limited
31、 by the capacity of transportation and erection equipment. The crane is the most common type of erection equipment, but when a structure is too high or extensive in area to be erected by a crane, it is necessary to place one or more derricks on the structure to handle the steel. In high structures t
32、he derrick must be constantly dismantled and reerected to successively higher levels to raise the structure. For river bridges the steel may be handled by cranes on barges, or, if the bridge is too high, by traveling derricks which ride on the bridge being erected, Cables for long suspension bridges
33、 are assembled in place by special equipment that pulls the wire from a reel, set up at one anchorage, across to the opposite anchorage, repeating the operation until the bundle of wires is of the required size.Concrete construction. Concrete construction consists of several operations: forming, con
34、crete production, placement, and curing. Forming is required to contain and support the fluid concrete within its desired final outline until it solidifies and can support itself. The form is made of timber or steel sections or a combination of both and is held together during the concrete placing b
35、y external bracing or internal ties. The forms and ties are designed to withstand the temporary fluid pressure of the concrete.The usual practice for vertical walls is to leave the forms in position for at least a day after the concrete is placed. They are removed when the concrete has solidified or
36、 set. Slip-forming is a method where the form is constantly in motion, just ahead of the level of fresh concrete. The form is lifted upward by means of jacks which are mounted on vertical rods embedded in the concrete and are spaced along the perimeter of the structure. Slip forms are used for high
37、structures such as silos, tanks, or chimneys.Concrete may be obtained from commercial batch plants which deliver it in mix trucks if the job is close to such a plant, or it may be produced at the job site. Concrete production at the job site requires the erection of a mixing plant, and of cement and
38、 aggregate receiving and handling plants. Aggregates are sometimes produced at or near the job site. This requires opening a quarry and erecting processing equipment such as crushers and screens.Concrete is placed by chuting directly from the mix truck, where possible, or from buckets handled by mea
39、ns of cranes or cableways, or it can be pumped into place by special concrete pumps.Curing of exposed surfaced is required to prevent evaporation of mix water or to replace moisture that dose evaporate. The poper blance of water and cement is required to develop full design strength.Concrete paving
40、for airports and highways is a fully mechanized operation. Batches of concrete are placed between the road forms from a mix truck or a movable paver, which is a combination mixer and placer. A series of specialized pieces of equipment, which ride on the forms, follow to spread and vibrate the concre
41、te, smooth its surface, cut contraction joints, and apply a curing compound.Asphalt paving. This is an amalgam of crushed aggregate and a bituminous binder. It may be placed on the roadbed in separate operations or mixed in a mix plant and spread at one time on the roadbed. Then the pavement is comp
42、acted by rollers.建筑工程摘要：建筑工程是土木工程的一个专业分支，涉及对诸如高速公路、建筑物、水坝、机场和公用事业管线项目的规划、实施和控制。规划包括安排工作完成和选择最适合于工程的施工方法和设备。实施需要对所以工作中的图纸、布局和物料的及时准备，以防止对工期的延误。控制包括分析进度和确定成本，以至于工程可以按计划进行并且在估算的成本范围内。关键词：规划，实施，控制，现场准备，土方工程，地基处理，混凝土施工，沥青铺设等。建筑工程是土木工程的一个专业分支，涉及对诸如高速公路、建筑物、水坝、机场和公用事业管线项目的规划、实施和控制。规划包括安排工作完成和选择最适合于工程的施工方法和
43、设备。实施需要对所以工作中的图纸、布局和物料的及时准备，以防止对工期的延误。控制包括分析进度和确定成本，以至于工程可以按计划进行并且在估算的成本范围内。规划 规划阶段开始于一个详细的施工方案和规范。通过这个研究，一系列项工程做好准备,并且相关项目组合在一起列成主要进度表。一系列的建设和时间分配到各个项目就是那么表示的。选择用于单个工作项目的操作方法和设备, 以尽可能低的成本来满足项目的进度和特点。那种特定操作的时间分配数量以及操作方法和设备的选择对承包商是相当有用的。总监或一般的施工进度制定出来之后，准备辅助的详细计划或预测报告。这些包括取得原材料、设备、劳动力的单个时间表,以及预算成本和收入
44、。实施 快速实施工程要求所有材料、设备、劳动力在需要时能及时供应。建筑工程师是通常负责工程中购买整个过程中大部分的建筑材料,并且迅速完成运输。有些材料,例如结构钢和机械设备,要求部分或全部由供应商制作。对于这些加工材料，工程师必须准备或检查所有生产图纸的准确性以及装配情况和经常检查供应商的制造。其他建设工程的责任是用调查法布局工作，制备的节点详图阐明了设计工程师为施工队伍准备的施工图纸，以及检验人员的工作,以确保它符合计划和规范。在大多数大型项目中,准备和设计临时建筑设施的施工图纸是必要的,例如排水结构、进出道路、办公室和存储建筑物、模板和围堰。其他问题是选择电气与机械设备和具体设计混凝土原料
45、加工与搅拌厂以及压缩空气、水和电气配电系统。控制 进度控制是通过比较工程实际进度与主要进度表中确定的预期进度来进行的。因为延迟某一项工作很容易影响到整个工作,所以常常需要增加设备或人员以加快工作进度。成本控制是比较单个工作项目的实际单价与预期或预算单价，在开始工作时设立。一个单位成本用项目总成本除以项目单位数量。立方公尺深是土方工程或混凝土工程的标准单位，还有钢结构的标准单位是吨。实际的单位成本在任何时间任何项目以用于该项目的积累成本除以完成工作的积累单位。单个项工作成本通过定期分配工作需要耗费到各个工作项账目而得到，例如工资和发票的方式。工资和设备租赁费用分布与援助的时间卡由包工头准备。卡片
46、注明工作人员和设备在不同的施工项目中的消耗。材料成本的分配是基于每一种材料应用于每个具体项目数量。当比较实际和预计单位成本表明了超支时；分析了核实事件的原因。如果超支在设备的费用,可能是设备生产能力不足,或是不太好使了。如果超支在劳动力成本,可能是队员们的人太多,缺乏适当的监督、或正在被耽搁由于缺乏材料或布局。在这种情况下，在分析研究生产率时工时研究是非常宝贵的。施工操作一般都是根据专门领域进行分类。这些包括准备工程项目的工地,土方工程机械、地基处理、钢结构安装、混凝土浇筑、沥青路面铺设,和机电安装。这些领域的每一个程序通常是同样的,即使应用到不同的项目,如建筑、大坝、或机场。然而,各个领域的
47、相对重要性不是在所有的情况下都一样的。现场准备 它是清除将建建筑物所在地点的表面建筑物和生长物。一辆推土机用于小型结构和树木。更大的结构必须被拆除。土方工程 这包括开挖以及土方回填。开挖遵循现场的准备工作,当现有地面下降到一个新的高度就完成了。开挖一般从分批移除有机的表层土壤开始,这是后来再用于周围新结构的园林绿化。这也防止低于表土层和要求回填的无机材料的污染。开挖可以用多种挖掘设备挖掘,如铁铲式挖掘机、拉铲式挖掘机、抓斗式挖掘机、起重式挖掘机和铲运式挖掘机。在陆地上有效的开挖需要干燥的挖掘环境,因为许多土壤在湿的时候是不稳定的,不能支持的挖掘和搬运设备。当开挖低于自然水位线和拦截地下水流时，
48、排水成为最主要工作。当这种情况发生时,排水和稳定的土壤可能需要通过设置排水沟用以引导渗流水到集水坑,再从集水坑抽走。排水和稳定的土壤可能在其他情况下用井点和电渗滤水来完成。有些材料,如岩石、胶结砂砾和硬粘土,要求孔爆破松动及分裂材料。爆破孔就是在材料中钻孔，爆炸物是放置在爆破孔中，然后引爆。炸药的数量和爆破孔间距依赖岩石的类型及结构和爆破孔的直径与深度。土方回填后,几乎都需要打夯以防止之后的沉降。打夯一般做实夯实机、压路机、充气轮胎式打夯机、振动式打夯机、轮压式打夯机，就是用拖拉机牵引把土方回填。 手持式和气动式夯锤用来夯实那些临近结构没有空间给碾压机操作的地方。地基处理 当地质勘察表明在基础
49、区域将被用于结构的有结构缺陷的,地基必须加强。水通道、洞穴、裂缝、断层和其他缺陷可以通过灌浆来填充加强。灌浆由加压注射流体混合物。这些流质随后在地层空隙中固化。大多数灌浆是水与水泥的混合物,或者其他混合原料沥青、水泥和粘土,还有沉淀的化学物质。钢安装。构建钢结构包括组装在现场扎制的钢筋或工厂装配。 钢部分由梁、柱、或用铆接、螺栓或焊接方式连接在一起的小桁架组成的。结构的大部分区域由工厂预制是更经济的，而不是现场制作，不过预制单个构件被运输和安装设备限制的。吊车是最常见的安装设备,但是当用吊车去安装过高或面积过于大的结构时，有必要在结构上设置一个或多个转臂式起重机一种最简单的起重机竖起来。在较高结构物上的转臂式起重机要时常拆除再重新安装，上升到一定水平来吊装结构。河流上有桥梁的，钢结构用起重机吊装在平地船上,或者,如果桥太高,将移动式起重机安装在桥上。大跨度的钢索桥装配是通过从卷轴拉动钢丝的某种设备，从而建立一个锚固端,将力传达给另一端,重复这一工作直到钢绞线变成需要的尺寸。混凝土施工 混凝土施工包括
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