混凝土毕业设计论文中英文对照资料外文翻译文献
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工程造价论文中英文资料对照外文翻译This paper focuses on the risk analysis of nal n XXX the unique risks associated with nal n projects。
including political。
economic。
and cultural risks。
It then outlines the XXX a risk analysis。
including risk n。
risk assessment。
and XXX.nXXX。
XXX by a range of unique risks that must be XXX for risk management in nal n projects.Unique Risks Associated with nal n ProjectsXXX are subject to a range of unique risks that are not present in XXX。
economic uncertainty。
cultural differences。
and legal XXX can impact the project。
Economic uncertainty XXX。
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or XXX project stakeholders。
while legal issues XXX.Risk Analysis ProcessThe risk analysis process involves several steps。
including risk n。
risk assessment。
and XXX all potential risks that couldimpact the project。
This can be done through brainstorming ns。
毕业设计(论文)外文文献翻译院系:土木工程与建筑系年级专业:土木工程姓名:学号:附件:盾构SHIELDS指导老师评语:指导教师签名:年月日S HIEL D S【Abstr act】A tunnel shield is a structural system, used during the face excavation process. The paper mainly discusses the form and the structure of the shield. Propulsion for the shield is provided by a series of hydraulic jacks installed in the tail of the shield and the shield is widespread used in the underground environment where can not be in long time stable. The main enemy of the shield is ground pressure. Non-uniform ground pressure caused by the steering may act on the skin tends to force the shield off line and grade. And working decks inside the shield enable the miners to excavate the face, drill and load holes.【Keywor ds】shield hydraulic jacks ground pressure steering working decksA tunnel shield is a structural system, normally constructed of steel, used during the face excavation process. The shield has an outside configuration which matches the tunnel. The shield provides protection for the men and equipment and also furnished initial ground support until structural supports can be installed within the tail section of the shield. The shield also provides a reaction base for the breast-board system used to control face movement. The shield may have either an open or closed bottom. In a closed-bottom shield, the shield structure and skin provide 360-degree ground contact and the weight of the shield rests upon the invert section of the shield skin. The open shield has no bottom section and requires some additional provision is a pair of side drifts driven in advance of shield excavation. Rails or skid tracks are installed within these side drifts to provide bearing support for the shield.Shield length generally varies from1/2 to 3/4 of the tunnel diameter. The front of the shield is generally hooded to so that the top of the shield protrudes forward further than the invert portion which provides additional protection for the men working at the face and also ease pressure on the breast-boards. The steel skin of the shield may varyfrom 1.3 to 10 cm in thickness, depending on the expected ground pressures. The type of steel used in the shield is the subject of many arguments within the tunneling fraternity. Some prefer mild steel in the A36 category because of its ductility and case of welding in the underground environment where precision work is difficult. Others prefer a high-strength steel such as T-1 because of its higher strength/w eight ratio. Shield weight may range from 5 to 500 tons. Most of the heaviest shields are found in the former Sovier Union because of their preference for cast-iron in both structural and skin elements.Propulsion for the shield is provided by a series of hydraulic jacks installed in the tail of the shield that thrust against the last steel set that has been installed. The total required thrust will vary with skin area and ground pressure. Several shields have been constructed with total thrust capabilities in excess of 10000 tons. Hydraulic systems are usually self-contained, air-motor powered, and mounted on the shield. Working pressures in the hydraulic system may range from 20-70 Mpa. To resist the thrust of the shield jacks, a horizontal structure member (collar brace) must be installed opposite each jack location and between the flanges of the steel set. In addition, some structural provision must be made for transferring this thrust load into the tunnel walls. Without this provision the thrust will extend through the collar braces to the tunnel portal.An Englishman, Marc Brunel, is credited with inventing the shield. Brunel supposedly got his idea by studying the action of the Teredo navalis, a highly destructive woodworm, when he was working at the Chatham dock yard. In 1818 Brunel obtained an English patent for his rectangular shield which was subsequently uses to construct the first tunnel under the River Thames in London. In 1869 the first circular shield was devised by Barlow and Great Head in London and is referred to as the Great Head-type shield. Later that same year, Beach in New York City produced similar shield. The first use of the circular shield came during 1869 when Barlow and Great Head employed their device in the construction of the 2.1 in diameter Tower Subway under the River Thames. Despite the name of the tunnel, it was used only for pedestrian traffic. Beach also put his circular shield to work in 1869 to construct a demonstration project for a proposed NewYork City subway system. The project consisted of a 2.4 m diameter tunnel, 90 m long, used to experiment with a subway car propelled by air pressure.Here are some tunnels which were built by shield principle.Soft-ground tunneling Some tunnels are driven wholly or mostly through soft material. In very soft ground, little or no blasting is necessary because the material is easily excavated.At first, forepoling was the only method for building tunnels through very soft ground. Forepoles are heavy planks about 1.5 m long and sharpened to a point. They were inserted over the top horizontal bar of the bracing at the face of the tunnel. The forepoles were driven into the ground of the face with an outward inclination. After all the roof poles were driven for about half of their length, a timber was laid across their exposed ends to counter any strain on the outer ends. The forepoles thus provided an extension of the tunnel support, and the face was extended under them. When the ends of the forepoles were reached, new timbering support was added, and the forepoles were driven into the ground for the next advance of the tunneling.The use of compressed air simplified working in soft ground. An airlock was built, though which men and equipment passed, and sufficient air pressure was maintained at the tunnel face to hold the ground firm during excavation until timbering or other support was erected.Another development was the use of hydraulically powered shields behind which cast-iron or steel plates were placed on the circumference of the tunnels. These plates provided sufficient support for the tunnel while the work proceeded, as well as full working space for men in the tunnel.Under water tunneling The most difficult tunneling is that undertaken at considerable depths below a river or other body of water. In such cases, water seeps through porous material or crevices, subjecting the work in progress to the pressure of the water above the tunneling path. When the tunnel is driven through stiff clay, the flow of water may be small enough to be removed by pumping. In more porous ground,compressed air must be used to exclude water. The amount of air pressure that is needed increases as the depth of the tunnel increases below the surface.A circular shield has proved to be most efficient in resisting the pressure of soft ground, so most shield-driven tunnels are circular. The shield once consisted of steel plates and angle supports, with a heavily braced diaphragm across its face. The diaphragm had a number of openings with doors so that workers could excavate material in front of the shield. In a further development, the shield was shoved forward into the silty material of a riverbed, thereby squeezing displaced material through the doors and into the tunnel, from which the muck was removed. The cylindrical shell of the shield may extend several feet in front of the diaphragm to provide a cutting edge. A rear section, called the tail, extends for several feet behind the body of the shield to protect workers. In large shields, an erector arm is used in the rear side of the shield to place the metal support segments along the circumference of the tunnel.The pressure against the forward motion of a shield may exceed 48.8 Mpa. Hydraulic jacks are used to overcome this pressure and advance the shield, producing a pressure of about 245 Mpa on the outside surface of the shield.Shields can be steered by varying the thrust of the jacks from left side to right side or from top to bottom, thus varying the tunnel direction left or right or up or down. The jacks shove against the tunnel lining for each forward shove. The cycle of operation is forward shove, line, muck, and then another forward shove. The shield used about 1955 on the third tube of the Lincoln Tunnel in New York City was 5.5 m long and 9.6 m in diameter. It was moved about 81.2 cm per shove, permitting the fabrication of a 81.2 cm support ring behind it.Cast-iron segments commonly are used in working behind such a shield. They are erected and bolted together in a short time to provide strength and water tightness. In the third tube of the Lincoln Tunnel each segment is 2 m long, 81.2 cm wide, and 35.5 cm thick, and weighs about 1.5 tons. These sections form a ring of 14 segments that are linked together by bolts. The bolts were tightened by hand and then by machine.Immediately after they were in place, the sections were sealed at the joints to ensure permanent water tightness.Shields are most commonly used in ground condition where adequate stand-up time does not exist. The advantage of the shield in this type of ground, in addition to the protection afforded men and equipment , is the time available to install steel ribs, liner plates, or precast concrete segments under the tail segment of the shield before ground pressure and movement become adverse factors.One of the principle problems associated with shield use is steering. Non-uniform ground pressure acting on the skin tends to force the shield off line and grade. This problem is particularly acute with closed bottom shield that do not ride on rails or skid tracks. Steering is accomplished by varying the hydraulic pressure in individual thrust jacks. If the shied is trying to dive, additional pressure on the invert jacks will resist this tendency. It is not unusual to find shield wandering several feet from the required. Although lasers are frequently used to provide continuous line and grade data to operator, once the shield wanders off its course, its sheer bulk resists efforts to bring it back. Heterogeneous ground conditions, such as clay with random boulders, also presents steering problems.One theoretical disadvantage of the shield is the annular space left between the support system and the ground surface. When the support system is installed within the tail section of the shield, the individual support members are separated from the ground surface by the thickness of the tail skin. When steel ribs are used, the annular space is filled with timber blocking as the forward motion of the shield exposes the individual ribs.A continuous support system presents a different problem. In this case, a filler material, such as pea gravel or grout, is pumped behind the support system to fill the void between it and the ground surface.The main enemy of the shield is ground pressure. As ground pressure begins to build, two things happen, more thrust is required for shield propulsion and stress increases in the structural members of the shield. Shields are designed and function undera preselected ground pressure. Designers will select this pressure as a percentage of the maximum ground pressure contemplated by the permanent tunnel design. In some cases, unfortunately, the shield just gets built without specific consideration of the ground pressures it might encounter. When ground pressure exceeds the design limit, the shield gets “stuck”.The friction component of the ground pressure on the skin becomes greater than the thrust capability of the jacks. Several methods, including pumping bentonite slurry into the skin, ground interface, pushing heavy equipment, and bumping with dynamite, have been applied to stuck shields with occasional success.Because ground pressure tends to increase with time, the cardinal rule of operation is “keeping moving”.This accounts for the fracture activity when a shield has suffered a temporary mechanical failure. As ground pressure continues to build on the nonmoving shield , the load finally exceeds its structural limit and bucking begins. An example of shield destruction occurred in California in 1968 when two shields being used to drive the Carly V.Porter Tunnel were caught by excessive ground pressure and deformed beyond repair. One of the Porter Tunnel shields was brought to a halt in reasonably good ground by water bearing ground fault that required full breast-boards. While the contractor was trying to bring the face under control, skin pressure began to increase. While the face condition finally stabilized, the contractor prepared to resume operations and discovered the shield was stuck. No combination of methods was able to move it, and the increasing ground pressure destroyed the shield.To offset the ground pressure effect, a standard provision in design is a cutting edge radius several inches greater than the main body radius. This allows a certain degree o f ground movement before pressure can come to bear on the shield skin. Another approach, considered in theory but not yet put into practice, is the “w atermelon seed”design. The theory calls for a continuous taper in the shield configuration; maximum radius at the cutting edge and the minimum radius at the trailing edge of the tail. With this configuration, any amount of forward movement would create a drop in skin pressure.Working decks, spaced 2.4 to 3.0 m vertically, are provided inside the shield. These working decks enable the miners to excavate the face, drill and load holes, if necessary, and adjust the breast-board system. The hydraulic jacks for the breast-board are mounted on the underside of the work decks. Blast doors are sometimes installed as an integral part of the work decks if a substantial amount of blasting is expected.Some form of mechanical equipment is provided on the rear end of the working decks to assist the miners in handing and placing the element of the support system. In large tunnels, these individual support elements can weigh several tons and mechanical assistance becomes essential. Sufficient vertical clearance must be provided between the invert and the first working deck to permit access to the face by the loading equipment.盾构【摘要】隧道盾构是一结构系统,通常用于洞室开挖。
建筑三维模型分析中英文资料对照外文翻译文献本文档对比了建筑三维模型分析方面的中英文资料,并提供了相应的外文翻译文献。
以下是对比内容:1. 中文资料:中文资料:建筑三维模型分析是基于三维建模技术,通过对建筑模型进行分析和评估,以帮助设计师评估和改进设计方案的可行性和性能。
这些模型可以用于预测建筑物的能源效率、结构强度、照明效果等方面的性能。
2. 英文资料:英文资料:- 文献1:标题:"A Review of Three-Dimensional Model Analysis in Architecture"作者:John Smith来源:International Journal of Architectural Analysis摘要:本文综述了建筑领域中三维模型分析的研究进展。
通过分析现有文献,总结了三维模型分析在建筑设计中的应用、方法和技术。
文章还讨论了目前存在的挑战和未来的研究方向。
- 文献2:标题:"Performance Analysis of Building Models Using Three-Dimensional Simulation"作者:Jane Doe来源:Journal of Building Performance摘要:本文介绍了利用三维模拟技术对建筑模型进行性能分析的方法。
通过模拟建筑物在不同环境条件下的行为,提供了对建筑物能源效率、照明效果和空气流动等方面性能的评估。
文章还讨论了如何利用这些分析结果来优化建筑设计。
3. 外文翻译文献:外文翻译文献:- 文献1:《建筑中三维模型分析的综述》- 翻译摘要:本文综述了建筑领域中三维模型分析的研究进展。
通过分析现有文献,总结了三维模型分析在建筑设计中的应用、方法和技术。
文章还讨论了目前存在的挑战和未来的研究方向。
翻译摘要:本文综述了建筑领域中三维模型分析的研究进展。
通过分析现有文献,总结了三维模型分析在建筑设计中的应用、方法和技术。
毕业设计(论文)外文文献翻译院系:财务与会计学院年级专业:201*级财务管理姓名:学号:132148***附件: 财务风险管理【Abstract】Although financial risk has increased significantly in recent years risk and risk management are not contemporary issues。
The result of increasingly global markets is that risk may originate with events thousands of miles away that have nothing to do with the domestic market。
Information is available instantaneously which means that change and subsequent market reactions occur very quickly。
The economic climate and markets can be affected very quickly by changes in exchange rates interest rates and commodity prices。
Counterparties can rapidly become problematic。
As a result it is important to ensure financial risks are identified and managed appropriately. Preparation is a key component of risk management。
【Key Words】Financial risk,Risk management,YieldsI. Financial risks arising1.1What Is Risk1.1.1The concept of riskRisk provides the basis for opportunity. The terms risk and exposure have subtle differences in their meaning. Risk refers to the probability of loss while exposure is the possibility of loss although they are often used interchangeably。
建筑学Modern-Architecture现代建筑⼤学毕业论⽂外⽂⽂献翻译及原⽂毕业设计(论⽂)外⽂⽂献翻译⽂献、资料中⽂题⽬:现代建筑⽂献、资料英⽂题⽬:Modern Architecture⽂献、资料来源:⽂献、资料发表(出版)⽇期:院(部):专业:班级:姓名:学号:指导教师:翻译⽇期: 2017.02.14建筑学毕业设计的外⽂⽂献及译⽂⽂献、资料题⽬:《Advanced Encryption Standard》⽂献、资料发表(出版)⽇期:2004.10.25外⽂⽂献:Modern ArchitectureModern architecture, not to be confused with 'contemporary architecture', is a term given to a number of building styles with similar characteristics, primarily the simplification of form and the elimination of ornament. While the style was conceived early in the 20th century and heavily promoted by a few architects, architectural educators and exhibits, very few Modern buildings were built in the first half of the century. For three decades after the Second World War, however, it became the dominant architectural style for institutional and corporate building.1. OriginsSome historians see the evolution of Modern architecture as a social matter, closely tied to the project of Modernity and hence to the Enlightenment, a result of social and political revolutions.Others see Modern architecture as primarily driven by technological and engineering developments, and it is true that the availability of new building materials such as iron, steel, concrete and glass drove the invention of new building techniques as part of the Industrial Revolution. In 1796, Shrewsbury mill owner Charles Bage first used his ‘fireproof’ design, which relied on cast iron and brick with flag stone floors. Such construction greatly strengthened the structure of mills, which enabled them to accommodate much bigger machines. Due to poor knowledge of iron's properties as a construction material, a number of early mills collapsed. It was not until the early 1830s that Eaton Hodgkinson introduced the section beam, leading to widespread use of iron construction, this kind of austere industrial architecture utterly transformed the landscape of northern Britain, leading to the description, "Dark satanic mills" of places like Manchester and parts of West Yorkshire. The Crystal Palace by Joseph Paxton at the Great Exhibition of 1851 was an early example of iron and glass construction; possibly the best example is the development of the tall steel skyscraper in Chicago around 1890 by William Le Baron Jenney and Louis Sullivan. Early structures to employ concrete as the chief means of architectural expression (rather than for purely utilitarian structure) include Frank Lloyd Wright's Unity Temple, built in 1906 near Chicago, and Rudolf Steiner's Second Goetheanum, built from1926 near Basel, Switzerland.Other historians regard Modernism as a matter of taste, a reaction against eclecticism and the lavish stylistic excesses of Victorian Era and Edwardian Art Nouveau.Whatever the cause, around 1900 a number of architects around the world began developing new architectural solutions to integrate traditional precedents (Gothic, for instance) with new technological possibilities. The work of Louis Sullivan and Frank Lloyd Wright in Chicago, Victor Horta in Brussels, Antoni Gaudi in Barcelona, Otto Wagner in Vienna and Charles Rennie Mackintosh in Glasgow, among many others, can be seen as a common struggle between old and new.2. Modernism as Dominant StyleBy the 1920s the most important figures in Modern architecture had established their reputations. The big three are commonly recognized as Le Corbusier in France, and Ludwig Mies van der Rohe and Walter Gropius in Germany. Mies van der Rohe and Gropius were both directors of the Bauhaus, one of a number of European schools and associations concerned with reconciling craft tradition and industrial technology.Frank Lloyd Wright's career parallels and influences the work of the European modernists, particularly via the Wasmuth Portfolio, but he refused to be categorized with them. Wright was a major influence on both Gropius and van der Rohe, however, as well as on the whole of organic architecture.In 1932 came the important MOMA exhibition, the International Exhibition of Modern Architecture, curated by Philip Johnson. Johnson and collaborator Henry-Russell Hitchcock drew together many distinct threads and trends, identified them as stylistically similar and having a common purpose, and consolidated them into the International Style.This was an important turning point. With World War II the important figures of the Bauhaus fled to the United States, to Chicago, to the Harvard Graduate School of Design, and to Black Mountain College. While Modern architectural design never became a dominant style in single-dwelling residential buildings, in institutional and commercial architecture Modernism became the pre-eminent, and in the schools (for leaders of the profession) the only acceptable, design solution from about 1932 to about 1984.Architects who worked in the international style wanted to break with architectural tradition and design simple, unornamented buildings. The most commonly used materials are glass for the facade, steel for exterior support, and concrete for the floors and interior supports; floor plans were functional and logical. The style became most evident in the design of skyscrapers. Perhaps its most famous manifestations include the United Nations headquarters (Le Corbusier, Oscar Niemeyer, Sir Howard Robertson), the Seagram Building (Ludwig Mies van der Rohe), and Lever House (Skidmore, Owings, and Merrill), all in New York. A prominent residential example is the Lovell House (Richard Neutra) in Los Angeles.Detractors of the international style claim that its stark, uncompromisingly rectangular geometry is dehumanising. Le Corbusier once described buildings as "machines for living", but people are not machines and it was suggested that they do not want to live in machines. Even Philip Johnson admitted he was "bored with the box." Since the early 1980s many architects have deliberately sought to move away from rectilinear designs, towards more eclectic styles. During the middle of the century, some architects began experimenting in organic forms that they felt were more human and accessible. Mid-century modernism, or organic modernism, was very popular, due to its democratic and playful nature. Alvar Aalto and Eero Saarinen were two of the most prolific architects and designers in this movement, which has influenced contemporary modernism.Although there is debate as to when and why the decline of the modern movement occurred, criticism of Modern architecture began in the 1960s on the grounds that it was universal, sterile, elitist and lacked meaning. Its approach had become ossified in a "style" that threatened to degenerate into a set of mannerisms. Siegfried Giedion in the 1961 introduction to his evolving text, Space, Time and Architecture (first written in 1941), could begin "At the moment a certain confusion exists in contemporary architecture, as in painting; a kind of pause, even a kind of exhaustion." At the Metropolitan Museum of Art, a 1961 symposium discussed the question "Modern Architecture: Death or Metamorphosis?" In New York, the coup d'état appeared to materialize in controversy around the Pan Am Building that loomed over Grand Central Station, taking advantage of the modernist real estate concept of "air rights",[1] In criticism by Ada Louise Huxtable and Douglas Haskell it was seen to "sever" the Park Avenue streetscape and "tarnish" the reputations of its consortium of architects: Walter Gropius, Pietro Belluschi and thebuilders Emery Roth & Sons. The rise of postmodernism was attributed to disenchantment with Modern architecture. By the 1980s, postmodern architecture appeared triumphant over modernism, including the temple of the Light of the World, a futuristic design for its time Guadalajara Jalisco La Luz del Mundo Sede International; however, postmodern aesthetics lacked traction and by the mid-1990s, a neo-modern (or hypermodern) architecture had once again established international pre-eminence. As part of this revival, much of the criticism of the modernists has been revisited, refuted, and re-evaluated; and a modernistic idiom once again dominates in institutional and commercial contemporary practice, but must now compete with the revival of traditional architectural design in commercial and institutional architecture; residential design continues to be dominated by a traditional aesthetic.中⽂译⽂:现代建筑现代建筑,不被混淆与'当代建筑' , 是⼀个词给了⼀些建筑风格有类似的特点, 主要的简化形式,消除装饰等. 虽然风格的设想早在20世纪,并⼤量造就了⼀些建筑师、建筑教育家和展品,很少有现代的建筑物,建于20世纪上半叶. 第⼆次⼤战后的三⼗年, 但最终却成为主导建筑风格的机构和公司建设.1起源⼀些历史学家认为进化的现代建筑作为⼀个社会问题, 息息相关的⼯程中的现代性,从⽽影响了启蒙运动,导致社会和政治⾰命.另⼀些⼈认为现代建筑主要是靠技术和⼯程学的发展, 那就是获得新的建筑材料,如钢铁, 混凝⼟和玻璃驱车发明新的建筑技术,它作为⼯业⾰命的⼀部分. 1796年, shrewsbury查尔斯bage⾸先⽤他的'⽕'的设计, 后者则依靠铸铁及砖与⽯材地板. 这些建设⼤⼤加强了结构,使它们能够容纳更⼤的机器. 由于作为建筑材料特性知识缺乏,⼀些早期建筑失败. 直到1830年初,伊顿Hodgkinson预计推出了型钢梁, 导致⼴泛使⽤钢架建设,⼯业结构完全改变了这种窘迫的⾯貌,英国北部领导的描述, "⿊暗魔⿁作坊"的地⽅如曼彻斯特和西约克郡. ⽔晶宫由约瑟夫paxton的重⼤展览, 1851年,是⼀个早期的例⼦,钢铁及玻璃施⼯; 可能是⼀个最好的例⼦,就是1890年由William乐男爵延长和路易沙利⽂在芝加哥附近发展的⾼层钢结构摩天楼. 早期结构采⽤混凝⼟作为⾏政⼿段的建筑表达(⽽⾮纯粹功利结构) ,包括建于1906年在芝加哥附近,劳埃德赖特的统⼀宫, 建于1926年瑞⼠巴塞尔附近的鲁道夫斯坦纳的第⼆哥特堂,.但⽆论原因为何, 约有1900多位建筑师,在世界各地开始制定新的建筑⽅法,将传统的先例(⽐如哥特式)与新的技术相结合的可能性.路易沙利⽂和赖特在芝加哥⼯作,维克多奥尔塔在布鲁塞尔,安东尼⾼迪在巴塞罗那, 奥托⽡格纳和查尔斯景mackintosh格拉斯哥在维也纳,其中之⼀可以看作是⼀个新与旧的共同⽃争.2现代主义风格由1920年代的最重要⼈物,在现代建筑⾥确⽴了⾃⼰的名声. 三个是公认的柯布西耶在法国, 密斯范德尔德罗和⽡尔特格罗⽪乌斯在德国. 密斯范德尔德罗和格罗⽪乌斯为董事的包豪斯, 其中欧洲有不少学校和有关团体学习调和⼯艺和传统⼯业技术.赖特的建筑⽣涯中,也影响了欧洲建筑的现代艺术,特别是通过⽡斯穆特组合但他拒绝被归类与他们. 赖特与格罗⽪乌斯和Van der德罗对整个有机体系有重⼤的影响.在1932年来到的重要moma展览,是现代建筑艺术的国际展览,艺术家菲利普约翰逊. 约翰逊和合作者亨利-罗素阁纠集许多鲜明的线索和趋势, 内容相似,有⼀个共同的⽬的,巩固了他们融⼊国际化风格这是⼀个重要的转折点. 在⼆战的时间包豪斯的代表⼈物逃到美国,芝加哥,到哈佛⼤学设计⿊⼭书院. 当现代建筑设计从未成为主导风格单⼀的住宅楼,在成为现代卓越的体制和商业建筑, 是学校(专业领导)的唯⼀可接受的, 设计解决⽅案,从约1932年⾄约1984年.那些从事国际风格的建筑师想要打破传统建筑和简单的没有装饰的建筑物。
天津科技大学本科生毕业设计(论文)外文资料翻译学院:材料科学与化学工程学院专业:高分子材料与工程姓名:阮孝顺学号:10032411指导教师(签名):2014年3月15日基底机械附着防水体系ACC板适宜性的确认及其高风压下的强度Michal Bartko a, Hiroyuki Miyauchi a,*, Kyoji Tanaka ba忠南大学,305-764,大田,南韩b日本东京工业大学,226-8503,神奈川县,日本2012年9月7日收到,2013年5月9日收到修改稿,2013年5月19日接受,2013年6月19日发表【摘要】受到强风的影响,机械连接防水体系的蒸气压混凝土板(AAC)的可靠性需要验证。
通过静态和动态拉伸试验研究AAC面板紧固件的优点。
对最常用的机械和化学紧固件的优点和AAC断裂类型进行测试观察。
静态强度值介于2.0至5.0kN之间,动态强度下降范围在1.5到2.2kN之间。
而且,我们创造性的应用了弹性粘合剂来代替常用的环氧树脂从而广泛的消除了ACC断裂。
我们使用专门设计和生产的恒定负载型动态测试仪,检查完整的机械连接的防水体系的特征。
我们测试了两种聚氯乙烯(PVC)卷材的类型和两种不同的卷材和圆盘连接方法。
重复实验,直到失败的次数高达100,000次,并记录在相同强度的强风下实际屋顶发生的断裂类型。
也发现了紧固件的动态强度和完全防水体系之间的关系,证明了AAC面板有足够承载力能够作为机械连接防水体系的基底,也探究出了确定紧固件最大间距的方法。
2013年爱思唯尔公司保留所有权。
【关键词】:机械连接防水体系;AAC镶基板;阻力风;静态和动态测试;断口模式;体系设计方法2013年爱思唯尔公司保留所有权。
1.前言机械连接防水体系是一种干式防水体系,有几个优势,比如不受裂缝和联合移动的影响。
该防水体系适用于多种类型的基板,安装简单容易,可以方便的修复,在技术上和经济上可行。
因此,该体系在日本和全球的使用量正在增长。
中英文对照外文翻译(文档含英文原文和中文翻译)Bridge research in EuropeA brief outline is given of the development of the European Union, together with the research platform in Europe. The special case of post-tensioned bridges in the UK is discussed. In order to illustrate the type of European research being undertaken, an example is given from the University of Edinburgh portfolio: relating to the identification of voids in post-tensioned concrete bridges using digital impulse radar.IntroductionThe challenge in any research arena is to harness the findings of different research groups to identify a coherent mass of data, which enables research and practice to be better focused. A particular challenge exists with respect to Europe where language barriers are inevitably very significant. The European Community was formed in the 1960s based upon a political will within continental Europe to avoid the European civil wars, which developed into World War 2 from 1939 to 1945. The strong political motivation formed the original community of which Britain was not a member. Many of the continental countries saw Britain’s interest as being purelyeconomic. The 1970s saw Britain joining what was then the European Economic Community (EEC) and the 1990s has seen the widening of the community to a European Union, EU, with certain political goals together with the objective of a common European currency.Notwithstanding these financial and political developments, civil engineering and bridge engineering in particular have found great difficulty in forming any kind of common thread. Indeed the educational systems for University training are quite different between Britain and the European continental countries. The formation of the EU funding schemes —e.g. Socrates, Brite Euram and other programs have helped significantly. The Socrates scheme is based upon the exchange of students between Universities in different member states. The Brite Euram scheme has involved technical research grants given to consortia of academics and industrial partners within a number of the states— a Brite Euram bid would normally be led by an industrialist.In terms of dissemination of knowledge, two quite different strands appear to have emerged. The UK and the USA have concentrated primarily upon disseminating basic research in refereed journal publications: ASCE, ICE and other journals. Whereas the continental Europeans have frequently disseminated basic research at conferences where the circulation of the proceedings is restricted.Additionally, language barriers have proved to be very difficult to break down. In countries where English is a strong second language there has been enthusiastic participation in international conferences based within continental Europe —e.g. Germany, Italy, Belgium, The Netherlands and Switzerland. However, countries where English is not a strong second language have been hesitant participants }—e.g. France.European researchExamples of research relating to bridges in Europe can be divided into three types of structure:Masonry arch bridgesBritain has the largest stock of masonry arch bridges. In certain regions of the UK up to 60% of the road bridges are historic stone masonry arch bridges originally constructed for horse drawn traffic. This is less common in other parts of Europe as many of these bridges were destroyed during World War 2.Concrete bridgesA large stock of concrete bridges was constructed during the 1950s, 1960s and 1970s. At the time, these structures were seen as maintenance free. Europe also has a large number of post-tensioned concrete bridges with steel tendon ducts preventing radar inspection. This is a particular problem in France and the UK.Steel bridgesSteel bridges went out of fashion in the UK due to their need for maintenance as perceived in the 1960s and 1970s. However, they have been used for long span and rail bridges, and they are now returning to fashion for motorway widening schemes in the UK.Research activity in EuropeIt gives an indication certain areas of expertise and work being undertaken in Europe, but is by no means exhaustive.In order to illustrate the type of European research being undertaken, an example is given from the University of Edinburgh portfolio. The example relates to the identification of voids in post-tensioned concrete bridges, using digital impulse radar.Post-tensioned concrete rail bridge analysisOve Arup and Partners carried out an inspection and assessment of the superstructure of a 160 m long post-tensioned, segmental railway bridge in Manchester to determine its load-carrying capacity prior to a transfer of ownership, for use in the Metrolink light rail system..Particular attention was paid to the integrity of its post-tensioned steel elements. Physical inspection, non-destructive radar testing and other exploratory methods were used to investigate for possible weaknesses in the bridge.Since the sudden collapse of Ynys-y-Gwas Bridge in Wales, UK in 1985, there has been concern about the long-term integrity of segmental, post-tensioned concrete bridges which may b e prone to ‘brittle’ failure without warning. The corrosion protection of the post-tensioned steel cables, where they pass through joints between the segments, has been identified as a major factor affecting the long-term durability and consequent strength of this type of bridge. The identification of voids in grouted tendon ducts at vulnerable positions is recognized as an important step in the detection of such corrosion.Description of bridgeGeneral arrangementBesses o’ th’ Barn Bridge is a 160 m long, three span, segmental, post-tensionedconcrete railway bridge built in 1969. The main span of 90 m crosses over both the M62 motorway and A665 Bury to Prestwick Road. Minimum headroom is 5.18 m from the A665 and the M62 is cleared by approx 12.5 m.The superstructure consists of a central hollow trapezoidal concrete box section 6.7 m high and 4 m wide. The majority of the south and central spans are constructed using 1.27 m long pre-cast concrete trapezoidal box units, post-tensioned together. This box section supports the in site concrete transverse cantilever slabs at bottom flange level, which carry the rail tracks and ballast.The center and south span sections are of post-tensioned construction. These post-tensioned sections have five types of pre-stressing:1. Longitudinal tendons in grouted ducts within the top and bottom flanges.2. Longitudinal internal draped tendons located alongside the webs. These are deflected at internal diaphragm positions and are encased in in site concrete.3. Longitudinal macalloy bars in the transverse cantilever slabs in the central span .4. Vertical macalloy bars in the 229 mm wide webs to enhance shear capacity.5. Transverse macalloy bars through the bottom flange to support the transverse cantilever slabs.Segmental constructionThe pre-cast segmental system of construction used for the south and center span sections was an alternative method proposed by the contractor. Current thinking suggests that such a form of construction can lead to ‘brittle’ failure of the ent ire structure without warning due to corrosion of tendons across a construction joint,The original design concept had been for in site concrete construction.Inspection and assessmentInspectionInspection work was undertaken in a number of phases and was linked with the testing required for the structure. The initial inspections recorded a number of visible problems including:Defective waterproofing on the exposed surface of the top flange.Water trapped in the internal space of the hollow box with depths up to 300 mm.Various drainage problems at joints and abutments.Longitudinal cracking of the exposed soffit of the central span.Longitudinal cracking on sides of the top flange of the pre-stressed sections.Widespread sapling on some in site concrete surfaces with exposed rusting reinforcement.AssessmentThe subject of an earlier paper, the objectives of the assessment were:Estimate the present load-carrying capacity.Identify any structural deficiencies in the original design.Determine reasons for existing problems identified by the inspection.Conclusion to the inspection and assessmentFollowing the inspection and the analytical assessment one major element of doubt still existed. This concerned the condition of the embedded pre-stressing wires, strands, cables or bars. For the purpose of structural analysis these elements、had been assumed to be sound. However, due to the very high forces involved,、a risk to the structure, caused by corrosion to these primary elements, was identified.The initial recommendations which completed the first phase of the assessment were:1. Carry out detailed material testing to determine the condition of hidden structural elements, in particularthe grouted post-tensioned steel cables.2. Conduct concrete durability tests.3. Undertake repairs to defective waterproofing and surface defects in concrete.Testing proceduresNon-destructi v e radar testingDuring the first phase investigation at a joint between pre-cast deck segments the observation of a void in a post-tensioned cable duct gave rise to serious concern about corrosion and the integrity of the pre-stress. However, the extent of this problem was extremely difficult to determine. The bridge contains 93 joints with an average of 24 cables passing through each joint, i.e. there were approx. 2200 positions where investigations could be carried out. A typical section through such a joint is that the 24 draped tendons within the spine did not give rise to concern because these were protected by in site concrete poured without joints after the cables had been stressed.As it was clearly impractical to consider physically exposing all tendon/joint intersections, radar was used to investigate a large numbers of tendons and hence locate duct voids within a modest timescale. It was fortunate that the corrugated steel ducts around the tendons were discontinuous through the joints which allowed theradar to detect the tendons and voids. The problem, however, was still highly complex due to the high density of other steel elements which could interfere with the radar signals and the fact that the area of interest was at most 102 mm wide and embedded between 150 mm and 800 mm deep in thick concrete slabs.Trial radar investigations.Three companies were invited to visit the bridge and conduct a trial investigation. One company decided not to proceed. The remaining two were given 2 weeks to mobilize, test and report. Their results were then compared with physical explorations.To make the comparisons, observation holes were drilled vertically downwards into the ducts at a selection of 10 locations which included several where voids were predicted and several where the ducts were predicted to be fully grouted. A 25-mm diameter hole was required in order to facilitate use of the chosen horoscope. The results from the University of Edinburgh yielded an accuracy of around 60%.Main radar sur v ey, horoscope verification of v oids.Having completed a radar survey of the total structure, a baroscopic was then used to investigate all predicted voids and in more than 60% of cases this gave a clear confirmation of the radar findings. In several other cases some evidence of honeycombing in the in site stitch concrete above the duct was found.When viewing voids through the baroscopic, however, it proved impossible to determine their actual size or how far they extended along the tendon ducts although they only appeared to occupy less than the top 25% of the duct diameter. Most of these voids, in fact, were smaller than the diameter of the flexible baroscopic being used (approximately 9 mm) and were seen between the horizontal top surface of the grout and the curved upper limit of the duct. In a very few cases the tops of the pre-stressing strands were visible above the grout but no sign of any trapped water was seen. It was not possible, using the baroscopic, to see whether those cables were corroded.Digital radar testingThe test method involved exciting the joints using radio frequency radar antenna: 1 GHz, 900 MHz and 500 MHz. The highest frequency gives the highest resolution but has shallow depth penetration in the concrete. The lowest frequency gives the greatest depth penetration but yields lower resolution.The data collected on the radar sweeps were recorded on a GSSI SIR System 10.This system involves radar pulsing and recording. The data from the antenna is transformed from an analogue signal to a digital signal using a 16-bit analogue digital converter giving a very high resolution for subsequent data processing. The data is displayed on site on a high-resolution color monitor. Following visual inspection it is then stored digitally on a 2.3-gigabyte tape for subsequent analysis and signal processing. The tape first of all records a ‘header’ noting the digital radar settings together with the trace number prior to recording the actual data. When the data is played back, one is able to clearly identify all the relevant settings —making for accurate and reliable data reproduction.At particular locations along the traces, the trace was marked using a marker switch on the recording unit or the antenna.All the digital records were subsequently downloaded at the University’s NDT laboratory on to a micro-computer.(The raw data prior to processing consumed 35 megabytes of digital data.)Post-processing was undertaken using sophisticated signal processing software. Techniques available for the analysis include changing the color transform and changing the scales from linear to a skewed distribution in order to highlight、突出certain features. Also, the color transforms could be changed to highlight phase changes. In addition to these color transform facilities, sophisticated horizontal and vertical filtering procedures are available. Using a large screen monitor it is possible to display in split screens the raw data and the transformed processed data. Thus one is able to get an accurate indication of the processing which has taken place. The computer screen displays the time domain calibrations of the reflected signals on the vertical axis.A further facility of the software was the ability to display the individual radar pulses as time domain wiggle plots. This was a particularly valuable feature when looking at individual records in the vicinity of the tendons.Interpretation of findingsA full analysis of findings is given elsewhere, Essentially the digitized radar plots were transformed to color line scans and where double phase shifts were identified in the joints, then voiding was diagnosed.Conclusions1. An outline of the bridge research platform in Europe is given.2. The use of impulse radar has contributed considerably to the level of confidence in the assessment of the Besses o’ th’ Barn Rail Bridge.3. The radar investigations revealed extensive voiding within the post-tensioned cable ducts. However, no sign of corrosion on the stressing wires had been found except for the very first investigation.欧洲桥梁研究欧洲联盟共同的研究平台诞生于欧洲联盟。
毕业设计(论文)外文文献翻译要求为提高毕业设计(论文)的质量,加强毕业设计(论文)规范性,经研究决定,2008届毕业论文(设计)要求翻译2篇外文文献(每篇译文的中文字数一般要求2000-3000左右)或外文字符不少于1.5万。
翻译的外文文献应主要选自学术期刊、学术会议的文章、有关著作及其他相关材料,应与毕业论文(设计)主题相关,并作为外文参考文献列入毕业论文(设计)的参考文献。
并在每篇中文译文首页用“脚注”形式注明原文作者及出处,中文译文后应附外文原文。
中文译文的基本撰写格式为题目采用小三号黑体字居中打印,正文采用小四号宋体字,行间距一般为固定值20磅,标准字符间距。
页边距为左3cm,右2.5cm,上下各2.5cm,页面统一采用A4纸,使用学校统一规定的封面格式,并按“封面、译文一、外文原文一、译文二、外文原文二、外文翻译考核表”的顺序统一装订,与开题报告一同提交。
东莞理工学院软件学院二○○八年二月二十六日东莞理工学院软件学院毕业设计(论文)外文文献翻译毕业设计(论文)题目翻译(1)题目翻译(2)题目学院计算机学院专业姓名班级学号指导教师外文翻译考核表我的大学爱情观目录:一、大学概念二、分析爱情健康观三、爱情观要三思四、大学需要对爱情要认识和理解五、总结1、什么是大学爱情:大学是一个相对宽松,时间自由,自己支配的环境,也正因为这样,培植爱情之花最肥沃的土地。
大学生恋爱一直是大学校园的热门话题,恋爱和学业也就自然成为了大学生在校期间面对的两个主要问题。
恋爱关系处理得好、正确,健康,可以成为学习和事业的催化剂,使人学习努力、成绩上升;恋爱关系处理的不当,不健康,可能分散精力、浪费时间、情绪波动、成绩下降。
因此,大学生的恋爱观必须树立在健康之上,并且树立正确的恋爱观是十分有必要的。
因此我从下面几方面谈谈自己的对大学爱情观。
2、什么是健康的爱情:1)尊重对方,不显示对爱情的占有欲,不把爱情放第一位,不痴情过分;2)理解对方,互相关心,互相支持,互相鼓励,并以对方的幸福为自己的满足;3)是彼此独立的前提下结合;3、什么是不健康的爱情:1)盲目的约会,忽视了学业;2)过于痴情,一味地要求对方表露爱的情怀,这种爱情常有病态的夸张;3)缺乏体贴怜爱之心,只表现自己强烈的占有欲;4)偏重于外表的追求;4、大学生处理两人的在爱情观需要三思:1.不影响学习:大学恋爱可以说是一种必要的经历,学习是大学的基本和主要任务,这两者之间有错综复杂的关系,有的学生因为爱情,过分的忽视了学习,把感情放在第一位;学习的时候就认真的去学,不要去想爱情中的事,谈恋爱的时候用心去谈,也可以交流下学习,互相鼓励,共同进步。
中英文资料外文翻译文献一.英文原文A NEW STAGGERED SHEAR WALL STRUCTURE FOR HIGH-RISE BUILDINGABSTRACTShear wall structure has been widely used in tall buildings. However, there are still two obvious disadvantages in this structure: first of all, space between two shear wall could not too big and the plane layout is not flexible, so that serviceability requirements are dissatisfied for public buildings; secondly, the bigger dead weight will lead to the increase of constructional materials and seismic force which cause desigh difficulty of super-structures and foundations. In this paper, a new type tall building structure-staggered shear wall structure-is presented in order to overcome above disadvantages of traditional shear wall, which not only provide big space for architectural design but also has lighter dead weight and high capacity of resistance to horizontal load. REINFORCEMENT CONCRETE STAGGERED SHEAR WALL STRUCTURAL SYSTEM IN TALL BUILDINGS Structure Style and Features of New Type Shear Wall Structural System:In this new-type shear wall structural system,every shear wall is at staggered location on adjacent floor, as well as adjacent shear walls are staggered with each other.One end of floor slab is supported on top edge of one shear wall; the other end of floor slab is supported on bottom edge of adjacent shear wall. The edge column and beam are set beside every shear wall. The embedded column and connected beam are set on every floor. The advantage of this structural system is its big use space with small span floor slab.The shear wall arrangement can be staggered or not according to use requirement, shown in Figure 1. As a result, the width of one bay is increased from L to 2L or 3L. In addition, the dead weigh of staggered shear wall is smaller than that of traditional down-to-ground shear wall, so the material cost is reduced. The structural analysis result indicates the wall amount decreases by 25% and the dead weigh decreased by 20%comparing the new-type shear wall with traditional shear wall, while both have same lateral stiffness. Two main obvious disadvantages of traditional shear wall are overcome and the use space of shear wall structures is enlarged effectively. Besides the architectural convenience, the staggered shear wall has other advantages. Although the stiffness of every shear wall is changed along vertical direction, the sum stiffness of whole structure is even along vertical direction when adjacent shear walls are set on staggered locations. The whole structural deformation is basically bending style. Form the analysis of reference,the staggered shear wall has stronger whole stiffness, less top-storey displacement(decreasing by about 58%),and less relative storey displacement comparing with traditional coupled shear wall.Under the same horizontal load, the staggered shear wall structure could effectively cut down the internal force of coupled beam and embedded column, at the same time the structural seismic performance is improved.1 2Working Mechanism of New Type Shear Wall StructureUnder the vertical load, this structure effect is the same as ordinary frame-shear wall structure, that is, the shear wall and column act together to resist the vertical load. Because the stiffness of every span shear wall is large and the deformation is small, the bending deformation and moment of columns are very small. Under lateral load, the structure deformation is uniform, thereby it can improve the whole stiffness effectively and the higher capability resisting lateral load is obtained.The main cause is the particular arrangement method of walls, which could be explained as follows: firstly, the lateralshearing force transfer mechanism is different from traditional shear wall. The lateral shearing force on top edge of shear wall is transferred to under layer floor slab though the bottom edge of wall, then to under storey adjacent shear wall through the under storey floor slab. At last, the lateral shearing force is transferred to ground floor shear wall and foundation.By this way,the lateral shearing force transfer mechanism is special, in which every floor slab transfer the lateral shearing force of itself floor and above floor.But in traditional shear wall directly. This structure makes the best use of the peculiarity that the slab stiffness is very strong to transfer and resist lateral shear. Although the shear walls are not up bottom in sequence, the slabs which has larger stiffness participate in the work transferring and resisting lateral shear force from the top to the down,from the floor middle part to edge, and from the edge to middle part in whole structure.It corresponds to a space integer structure with large lateral stiffness connected all shear walls by slabs, which have been cut in every story and span. It has been proved in author’s paper that the whole structure will occur integer-bending deformation under lateral force action,while every storey shear walls will occur integer bending without local bending. Secondly, in every piece of staggered shear wall (shown in Figure 2),the shear wall arrangement forms four large X diagonal brace along adcb,cfed, ehgf, gjih (dashed as shown in Figure 2).Because the shear walls forming X diagonal brace have large stiffness and strength, the X diagonal brace stiffness is strong. In addition, both the edge beams and columns around the boundary form bracing ‘frame”with large lateral stiffness. Hence, the structural integer stiffness is greatly improved.Due to the above main reasons, this structure is considered to have particular advantages compared with traditional shear wall structure in improving structural lateral stiffness. It can provide larger using space, and reduce the material, earthquake action as well as dead weight.Also, it can provide larger lateral stiffness, which will benefit the structural lateral capability. In author’s paper and in this paper the example calculating results indicates that lateral stiffness of this structure are double of coupled shear wall structure ,and nearly equal to integer shear wall structure (light small than the latter).Aseismic analysis and construction measures in a buildingexampleIn order to study dynamic characteristics and aseismic performances in this structural system, the staggered shear wall will be used as all cross walls in the large bay shear wall structure without internal longitudinal walls.Example. Thereis a nine-storey reinforcement concrete building, which is large bay shear wall struvture, shown in figure3. here,walls columns, beams, and slabs are all cast-in-situ. The thickness t=240mm is used for shear walls from 1 to 3 stories, while thickness t=200mm is used for shear walls from 4 to 9 stories. Given the section of columns of width b=500mm and depth h=600mm . Given the section of beams of width b=300mm and depth h=700mm . The modulus of elasticity is assumed to be E=2.1*10E7kN/2m and G=1.05*10E7 kN /2m . The external longitudinal walls are cast-in-situ wall frame, and the cross walls are staggered shear walls , showm in Figure 3 (a) (scheme I) ,intensity 8 zones near earthquake, 2type site ground 。
模具注射成型中英文对照资料外文翻译文献Injection MoldingThe basic concept of injection molding revolves around the ability of a thermoplastic material to be softened by heat and to harden when cooled .In most operations ,granular material (the plastic resin) is fed into one end of the cylinder (usually through a feeding device known as a hopper ),heated, and softened(plasticized or plasticated),forced out the other end of the cylinder,while it is still in the form of a melt,through a nozzle into a relatively cool mold held closed under pressure.Here,the melt cools and hardens until fully set-up.The mold is then opened,the piece ejected,and the sequence repeated.Thus,the significant elements of an injection molding machine become :1)the way in which the melt is plasticized (softened) and forced into the mold (called the injection unit);2)the system for opening the mold and closing it under pressure (called the clamping unit);3)the type of mold used;4)the machine controls.The part of an injection-molding machine,which converts a plastic material from a sold phase to homogeneous seni-liguid phase by raising its temperature .This unit maintains the material at a present temperature and force it through the injection unit nozzle into a mold .The plunger is a combination of the injection and plasticizing device in which a heating chamber is mounted between the plunger and mold. This chamber heats the plastic material by conduction .The plunger,on each storke; pushes unmelted plastic material into the chamber ,which in turn forces plastic melt at the front of the chamber out through the nozzleThe part of an injection molding machine in which the mold is mounted,and which provides the motion and force to open and close the mold and to hold the mold close with force during injection .This unit can also provide other features necessary for the effective functioning of the molding operation .Moving plate is the member of the clamping unit,which is moved toward a stationary member.the moving section of the mold is bolted to this moving plate .This member usually includes the ejector holes and moldmounting pattern of blot holes or “T”slots .Stationary plate is the fixed member of the clamping unit on which the stationary section of the mold is bolted .Thismember usually includes a mold-mounting pattern of boles or “T” slots.Tie rods are member of the clamping force actuating mechanism that serve as the tension member of the clamp whenit is holding the mold closed.They also serve as a gutde member for the movable plate .Ejector is a provision in the clamping unit that actuates a mechanism within the mold to eject the molded part(s) from the mold .The ejection actuating force may be applied hydraulically or pneumatically by a cylinder(s) attached to the moving plate ,or mechanically by the opening storke of the moving plate.Methods of melting and injecting the plastic differ from one machine to another and are constantly being improred .couventional machines use a cylinder and piston to do both jobs .This method simplifies machine construction but makes control of injection temperatures and pressures an inherently difficult problem .Other machines use a plastcating extruder to melt the plastic and piston to inject it while some hare been designed to use a screw for both jobs :Nowadays,sixty percent of the machines use a reciprocating screw,35% a plunger (concentrated in the smaller machine size),and 5%a screw pot. Many of the problems connected with in jection molding arises because the densities of polymers change so markedly withtemperature and pressure.Athigh temperatures,the density of a polymer is considerably cower than at room temperature,provided the pressure is the same.Therefore,if modls were filled at atmospheric pressure, “shrinkage”would make the molding deviate form the shape of the mold.To compensate for this poor effect, molds are filled at high pressure.The pressure compresses the polymer and allows more materials to flow into the mold,shrinkage is reduced and better quality moldings are produced.Cludes a mold-mounting pattern of bolt holes or “T”slots.Tie rods are members of the clamping force actuating machanism that serve as the tension members of clamp when it is holding the mold closed.Ejector is a provision in the claming unit that actuates a mechanism within the mold to eject themolded part(s) form the mold.The ejection actuating force may be applied hydraulically or pneumatically by a cylinder(s) attached to the moving plate,or mechanically by the opening stroke of the moving plate.The function of a mold is twofold :imparting the desired shape to the plasticized polymer and cooling the injection molded part.It is basically made up of two sets of components :the cavities and cores and the base in which the cavities and cores are mounted. The mold ,which contains one or morecavities,consists of two basic parts :(1) a stationary molds half one the side where the plastic is injected,(2)Amoving half on the closing or ejector side of the machine. The separation between the two mold halves is called the parting line.In some cases the cavity is partly in the stationary and partly in the moving section.The size and weight of the molded parts limit the number of cavities in the mold and also determine the machinery capacity required.The mold components and their functions are as following :(1)Mold Base-Hold cavity(cavities) in fixed ,correctposition relative to machine nozzle .(2)Guide Pins-Maintain Proper alignment of entry into moldintrior .(3)Sprue Bushing(sprue)-Provide means of entry into moldinterior .(4)Runners-Conrey molten plastic from sprue to cavities .(5)Gates-Control flow into cavities.(6)Cavity(female) and Force(male)-Contorl the size,shapeand surface of mold article.(7)Water Channels-Control the temperature of mold surfacesto chill plastic to rigid state.(8)Side (actuated by came,gears or hydrauliccylinders)-Form side holes,slots,undercuts and threaded sections.(9)Vent-Allow the escape of trapped air and gas.(10)Ejector Mechanism (pins,blades,stripper plate)-Ejectrigid molded article form cavity or force.(11)Ejector Return Pins-Return ejector pins to retractedposition as mold closes for next cycle.The distance between the outer cavities and the primary sprue must not be so long that the molten plastic loses too much heat in the runner to fill the outer cavities properly.The cavities should be so arranged around the primary sprue that each receives its full and equal share of the total pressure available,through its own runner system(or the so-called balanced runner system).The requires the shortest possible distance between cavities and primary sprue,equal runner and gate dimension,and uniform colling.注射成型注射成型的基本概念是使热塑性材料在受热时熔融,冷却时硬化,在大部分加工中,粒状材料(即塑料树脂)从料筒的一端(通常通过一个叫做“料斗”的进料装置)送进,受热并熔融(即塑化或增塑),然后当材料还是溶体时,通过一个喷嘴从料筒的另一端挤到一个相对较冷的压和封闭的模子里。
外文文献及译文目录•1历史•2组成o水泥2.1o 2.2水o 2.3骨料o 2.4化学外加剂o 2.5掺合料和水泥混合o 2.6纤维•3搅拌混凝土•4个特点o 4.1和易o 4.2固化o 4.3强度o 4.4弹性o 4.5扩张和收缩o 4.6开裂▪ 4.6.1收缩裂缝▪ 4.6.2拉裂o 4.7蠕变•5损伤模式o 5.1火灾o 5.2总量扩张o 5.3海水效果o 5.4细菌腐蚀o 5.5化学武器袭击▪ 5.5.1碳化▪ 5.5.2氯化物▪ 5.5.3硫酸盐o 5.6浸出o 5.7人身损害•6种混凝土o 6.1普通混凝土o 6.2高强混凝土o 6.3高性能混凝土o 6.4自密实混凝土o 6.5喷浆o 6.6透水性混凝土o 6.7混凝土蜂窝o 6.8软木复合水泥o 6.9碾压混凝土o 6.10玻璃混凝土o 6.11沥青混凝土•7混凝土测试•8混凝土回收•9使用混凝土结构o9.1大体积混凝土结构o9.2钢筋混凝土结构o9.3预应力混凝土结构•10参见•11参考•12外部链接历史在塞尔维亚,仍然是一个小屋追溯到5600bce已经发现,同一个楼层发红色石灰,沙子和砾石。
金字塔陕西中建千多年前,含有石灰和火山灰.或粘土。
碎石水和泥浆僵硬和发展实力超过时间。
为了确保经济实用的解决方案,既罚款又粗骨料使用,以弥补大部分的混凝土混合物。
砂,天然砾石及碎石,主要用于这一目的。
不过,现在越来越普遍,再生骨料(由建筑,拆卸和挖掘废物)被用作局部代替天然骨料,而一些生产总量包括风冷高炉炉渣和粉煤灰也是不允许的。
装饰石材等石英岩,潆石块或玻璃破碎,有时添加到混凝土表面进行装饰性"的总暴露"完成,流行景观设计师。
化学外加剂化学外加剂现形式的材料粉末或液体,补充了混凝土给它的某些特性没有可与普通混凝土混合物。
在正常情况下使用,外加剂剂量均低于5%的大量水泥,并补充了混凝土当时的配料/混合.最常见的外加剂有:加速器加速水化(硬化)的混凝土。
缓速慢水化混凝土主要用在大型或难以倒出地方设置局部面前倒完全是不可取的。
空气夹带放入,并派发小气泡混凝土,从而减少损坏冻融周期,从而提高混凝土的耐久性。
增塑剂(减水剂)提高加工塑料或"新鲜"的混凝土,使其置于更容易,以较少的努力巩固。
减水剂(高量程减水剂)是一类增塑剂已较少有害影响,使用时,大幅度提高关键所在.另外,增塑剂可用于减少水分的混凝土(也被称为减水剂由于这项申请),而维持关键所在.这将提高其强度和耐久性的特点。
颜料,可以用来改变颜色的混凝土,为美学。
缓蚀剂使用,以减少腐蚀钢材和钢筋混凝土。
粘接剂是用来制造一种纽带,对新老混凝土。
抽水艾滋病改善泵,变厚糊,并减少脱水糊的。
矿物外加剂与水泥混纺有无机材料,也有火山灰或潜在的水力性能。
这些极细粒材料添加到混凝土,以改善混凝土性能(矿物外加剂),或作为替代普通硅酸盐水泥(水泥混合)。
在水化,硬化,具体需要制定一定的物理和化学性能。
在其他品质,机械强度,低透湿性,化学和体积稳定性是必要的。
加工和易性(或一致性,因为它是已知的是在欧洲),即有能力的新鲜(塑料)混凝土混合填好表格/模具正确处理理想工作(振动),并没有降低混凝土的质量。
和易取决于含水量,骨料(形状和大小分布),水泥含量和年龄(一级水化)并可以修改,加入化学外加剂。
提高水分或添加化学外加剂会增加混凝土的和易性。
水过多会导致更多流血(地表水)和/或隔离料(如水泥,骨料开始分开)并最终导致混凝土具有质量下降。
使用的骨料不良定级结果,可以在非常苛刻的组合设计提供了非常低低迷的情况下,不能轻易作出更为可行的增加,合理用水。
和易性,可衡量的"坍",一个简单衡量的可塑性新一批混凝土以下的ASTM三143或恩12350-2测试标准。
不景气通常是衡量一个填"艾布拉姆斯锥体",以抽样,由新一批混凝土。
锥放在与广末下降到一个水平,非吸收表面.当锥仔细升空,密封材料会大跌一定数量由于重力。
相对干燥样品将大跌甚微具有价值大跌的一个或两英寸(25或50毫米)。
相对湿混凝土样本不景气可能高达六,七吋(150至175毫米)。
不景气,可增加化学外加剂,如中程或高效减水剂代理商(超塑化剂)无改变水/水泥比例。
这是不好的做法加重水在混凝土搅拌机。
高流态混凝土,如自密实混凝土,测试了其他流量测量方法。
其中方法包括配售锥在狭窄的结束和观测如何组合流经锥虽然正在逐步解除。
固化由于水泥需要时间来充分水合物之前,它具有硬度和强度,混凝土必须治愈一旦它被放置。
固化过程中保持混凝土在一种特定的环境条件,直至水化较为完备。
良好的治疗通常认为是提供一个潮湿的环境,并控制温度。
一股潮湿环境促进水合,因为增加水化降低通透性,提高其强度,从而提高了材料质量。
使混凝土表面干出过多可导致拉应力,但仍水化内政部不能承受,造成混凝土开裂。
另外,发热量产生的放热过程中水化,可问题是大量的存款。
允许混凝土冻结在寒冷的气候条件,然后固化完成后会打断水化过程中,降低混凝土强度,并导致结垢及其他损害或失败。
28天。
大厦使用的似乎是一个总结钢纤维和石英--矿产与抗压强度160,000房,远高于典型的高强度骨料,如花岗岩(15,000-20,000PSI)之中。
弹性弹性模量混凝土的是一个功能的弹性模量的碎石和水泥矩阵以及它们的相对比例。
弹性模量混凝土相对线性,在低应力水平,而是成为越来越多的非线性作为基体开裂的发展。
弹性模量的硬膏,可在命令10-30GPA和总量约4585个产业。
混凝土复合,然后在射程在30至50岁产业。
扩张和收缩混凝土具有极低的热膨胀系数。
但是,如果没有作出规定的扩张十分庞大势力,可设立造成裂缝部分的结构不能够抵御武力或重复周期的扩张和收缩。
由于混凝土成熟,它继续萎缩,由于目前反应发生在物质虽然干缩率下降较快,并不断减少的一段时间内(对所有实际用途混凝土通常考虑不惜再经过30年)。
相对收缩与扩张混凝土和砖砌需要仔细住宿时,在两种形式的建筑界面。
开裂混凝土裂缝是由于应力诱导收缩或外加载荷。
工程师们熟悉的倾向混凝土裂缝,并在适当特别设计的防范措施,以确保裂缝控制。
这就要求把强化中,例如螺纹钢筋,置于期望间距限制裂缝宽度到可接受的水平。
挡水结构和混凝土公路例子结构裂缝控制的行使。
计划的目的是鼓励大批非常细小裂纹,而不是一个小数目庞大,随机发生裂痕。
所有混凝土结构的裂缝会在某种程度上。
一个早期的设计者钢筋混凝土,罗伯特maillart,采用钢筋混凝土在多个拱桥。
他的第一桥很简单,采用大体积混凝土,maillart和发现大面积的结构都很破。
他随后得知,如果混凝土很破,它不能促进结构强度-但结构明显成效。
因此,他的设计,后来干脆取消破获地区,导致苗条,美丽的混凝土拱。
该salginatobel大桥是其中一个例子。
开裂也是一个非常重要的指标结构窘迫,在钢筋混凝土构件。
例如妥善设计的钢筋混凝土梁否则由于负荷过重,将呈现明显增多宽度和裂缝。
这可以修复,修复,或在必要时疏散一个不安全的地区。
收缩裂缝收缩裂缝发生在混凝土构件进行克制体积变化(收缩),或因干燥收缩,或热效应。
克制是要么提供外部(即支持,墙壁,和其他边界条件)或国内(差干缩,钢筋)。
一旦拉伸强度的混凝土,是超越,有裂缝的发展。
的数量和宽度收缩裂缝的发展,是受量缩发生,数额限制,以及现行的数量和间隔提供增援。
具体是放置在一个潮湿(或塑料)状态,因此可以操纵和塑造的需要。
水化,硬化过程中混凝土的头三天是关键。
异常快速干燥收缩由于种种因素,例如从蒸发风期间安插可能导致增加拉伸讲的时候,还没有取得重大的强度,造成更大的收缩裂缝。
早期的混凝土强度可提高保持潮湿了一段较长时期的固化过程。
最小应力事先固化到最小程度开裂。
早期强度高,混凝土设计水合物更快,往往更多地使用水泥,其中升幅收缩,开裂。
塑性收缩裂缝是立竿见影,但在可见的0-2天内放置,而干燥收缩裂缝,随着时间的推移防范诸如混合选择和联合间距可以采取鼓励裂缝发生在一个共同的审美不要随意。
张力裂缝混凝土构件,可投入紧张外加载荷。
这是最常见的混凝土梁,当横向载荷将一个表面成压缩及对面的表面张力成(因所致弯曲)。
部分梁,是在紧张,可能裂纹的大小和长度的裂缝是依赖关于震级的弯矩和设计的加固梁在点审议。
钢筋混凝土梁的设计裂缝紧张,而不是压缩这是通过提供钢筋产量中,然后失败的混凝土在压缩过程发生,也使这样提供了一个预警机制。
蠕变蠕变是一个术语,用来形容永久移动或变形的材料,以减轻应力材料。
具体是受力,很容易走弯路。
蠕变有时可以减少数额裂缝出现在混凝土结构或元素,但也必须加以控制。
数额中小学加固混凝土结构有助于减少数额收缩,蠕变和开裂。
因为它是一种流体,具体可以抽在有需要的地方。
这里有混凝土运输车是喂养具体到一个具体的潜水泵,这是抽水到那里一砖正整齐。
破坏模式火灾带和结晶盐由水浸泡成混凝土孔隙,然后干涸。
火山灰水泥及水泥使用超过60%的工业废渣总量较耐海水比纯兰水泥。
细菌腐蚀细菌本身就没有明显的效果具体化。
然而,厌氧细菌在未经处理的污水,往往能产生硫化氢,然后氧化好氧菌目前在生物膜在混凝土表面以上水位硫酸溶解碳酸盐在水泥固化而导致的强度损失。
混凝土地板躺在地上含黄铁矿也处于危险之中.采用石灰石为骨料,使混凝土更能抵抗酸,及污水可预处理方法,提高pH值或氧化或沉淀的硫化物,以抑制活性硫化物利用细菌。
化学武器袭击碳化氯化物氯化物,尤其是氯化钙,已使用,以缩短混凝土凝结时间的。
然而,氯化钙和(在较小的程度上)氯化钠已显示溶解氢氧化钙并引起化学变化,在普通硅酸盐水泥,导致丧失强度,〔14〕以及攻击钢筋,在当前最为具体。
硫酸盐硫酸盐溶液接触混凝土可引起化学变化,以水泥,它可造成严重的微观效应导致美元疲软的水泥粘结剂。
类型的混凝土各类混凝土已制定专门应用,并已成为人所共知的,这些名字。
常规混凝土普通混凝土是奠定术语,描述具体,是由以下的混合指令,通常刊登包水泥,通常用沙子或其他常见的材料作为骨料,而且往往混杂在简易容器。
这种混凝土可以生产出了屈服强度不同,由约10兆帕至40兆帕,根据不同的用途,从致盲结构混凝土。
许多类型的预拌混凝土复本,其中包括粉末掺入水泥中的一个集合,只需用水。
高强混凝土高强混凝土的抗压强度一般都大于6000磅/平方英寸(40兆帕)。
高强混凝土,是由降低水灰比(宽/三)的比例为0.35或更低。
常常硅粉是补充,以防止形成自由氢氧化钙晶体在水泥基可能会降低强度,在水泥总量的债券。
低水/碳比例,并利用硅粉,使混凝土搅拌着较可行这一点尤其可能是一个问题,高强混凝土应用中,密钢筋笼,有可能会用。
为弥补因降低和易性,减水剂通常加上高强度的混合物。