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外文文献及译文
文献、资料题目：Construction and Performance of Curtain Wall Systems for Super Highrise Buildings 文献、资料来源：网络
文献、资料发表（出版）日期：2007.4.5
院（部）：机电工程学院
专业：机械制造与自动化
班级：机械1121
姓名：
学号：
指导教师：
翻译日期：2014 年4 月20 日
外文文献：
Construction and Performance of Curtain Wall
Systems for Super Highrise Buildings
Raymond WM Wong
INTRODUCTION
The construction of super highrise buildings has been very active in Hong Kong for decades. Recent renowned projects like the 50-storey Manulife Tower, the 62-storey Cheung Kong Center, the 80-storey “Center”,the 88-storey International Financial Center, and a number of recent residential buildings exceeding 60-storey tall, are without exception, using curtain wall as their external envelope.
Using thin wall as external envelope for tall buildings has always been a challenge to designers and builders, in particular in terms of cost, energy, water-tightness, installation, dimensional and structural stability, interfacing arrangement with other building components and maintenance etc. Making use of the Hong Kong’s experience, the writer wish to highlight some local practices and summarize how such thin wall systems are designed and installed.
USING CURTAIN WALL IN BUILDIGNS OF HONG KONG
High-rise buildings started to spring up in the skyline of Hong Kong since the 1970’s in parallel with her economic take-off from a traditional manufacturing-based industrial economy and transforming herself into an world-renowned international financial centre. High-rise buildings by that time were concentrated in the commercial districts like Central in the Hong Kong Island and Tsim Sha Tsui on the Kowloon Peninsula side.
The first generation of buildings using what-so-called a curtain wall system can hardly be described as a full system which is usually of proprietary design. The pioneer systems were just external fa?ade/walling designed by local architects and with materials supplied by local
manufacturers. The common systems used by that time were in majority stick-type, spandrel and cover, or unit-in-frame systems, constructed of aluminum sections, sometimes incorporated with large areas of stone slabs to cover up solid walls. They were popular due to their highly adaptability, low cost, easy to design-and-install nature.
More deluxe commercial buildings were built in the late 70’s as the economy of Hong Kong growing hotter and hotter. Developers tended to request for systems with higher performance as the external envelop for their buildings, in terms both of appearance, material, construction and maintenance concerns.
Due to the relative lack of experience at that stage, the performance of these second generation curtain wall systems (from late 70’s to mid 80’s)could still hardly described as satisfactory. Problems like seepage, staining, deformation, deterioration and rapid aging of the jointing materials, were very common to many walling cases, often to a condition that made repair and maintenance almost impossible. The replacement of these walling systems not only costly, but also created great disruption to the normal utilization of the building users, and at the same time badly lowered the property value of the entire premises.
The third generation of curtain wall systems roughly started in the mid/late 80’s, by the time Hong Kong was experiencing her economic climax before the handing over of her sovereignty back
to China in 1997. Accommodated experience in the application of curtain wall systems in high-performance buildings contributed solidly in the process of perfecting these systems. Throughout the period, the design and production teams, as well as the manufacturers and the engineering supporting teams, were growing more mature in the mastering of the local situation and market. Most problems appeared in the previous cases have been much effectively taken care of. Systems of this generation are in general much more satisfactorily received by most users.
WHAT IS A CURTAIN WALL
Metal and glass curtain wall systems have found growing favour in modern architecture. They are easily distinguished from other types of claddings by their thin mullions of horizontal and vertical metallic bars surrounding an all glass or metal panel. The curtain wall system has evolved rapidly over the last two decades, especially with respect to weather control performance. The early systems presented frequent rain penetration problems; water stain patches would form on the outside or condensation on the inside mullion surfaces; glazing seals were sometimes pumped out of the rabbet of sealed double glazing window units. However, most of these difficulties were eventually overcome with improved detail design of the system components. Today, most curtain wall manufacturers offer a quality product line of components which can be used to create one of the best overall exterior wall systems.
A curtain wall system is a lightweight exterior cladding which is hung on the building structure, usually from floor to floor. It can provide a variety of exterior appearances but is characterized by narrowly spaced vertical and horizontal caps with glass or metal infill panels. These systems provide a finished exterior appearance and most often a semi-finished interior as well. They are also designed to accommodate structural deflections, control wind-driven rain and air leakage, minimize the effects of solar radiation and provide for maintenance-free long term performance. Most of today's metal curtain wall systems are constructed of lightweight aluminum or its alloys, although
some may be of steel.
COMMON TYPES OF CURTAIN WALL SYSTEMS
External wall with large area of glazed portion that carries no superimposed load except wind load is usually termed as curtain wall. Traditionally curtain wall consists of a metal frame system infill with vision or opaque panels, that serves to provide glazing for window openings as well as to cover-up structures like columns, slabs and beams, or sometimes even sections of solid wall.
There are many ways to serve the purpose, depending on a number of factors such as the design and budget for the project, layout and shape of the building structure, as well as other architectural or structural requirements. According to the American Architectural Manufacturers Association, curtain wall systems can be classified in five types, namely, the stick system, unit system, unit and mullion system, panel system, and the column-cover-and-spandrel system. However, due to the introduction of high-performance framing/articulation products and high-strength structural glass, some newer forms of curtain wall systems such as large-area glazed wall using spider clips, bow mullions, hangers or cable stiffeners as supports and connections, are new systems that cannot easily be classified using traditional concepts.
Stick system
Curtain wall in stick system is a cladding and exterior wall system which is hung on the building structure from floor to floor. It is assembled from various components to include steel or aluminum anchors, mullions (vertical load taking member), rails vision glass, spandrel panels, insulation and metal backing pans. For the fixing of the system, there are various hardware components such as anchors, connectors, brackets, cramps, setting blocks, corner blocks, gaskets and sealants etc.
This system has the following merits/demerits:
Merits
-Low cost, components can be made in standard design and stocked as proprietary product for use in bulk quantity.
-Shorter time for design and fabrication.
-Fairly easy to fit the shape and form of a building.
-Require relatively simple sections to form the mullions and the backing frame.
-The design of the infilling panels can be very flexible and form various combination using different materials to provide the appearance or fulfill other functional requirements.
-With the provision of the spandrel panel (the opaque portion) in the design, more colour or design options can be achieved.
-Installation of the system only requires simple tool like a manually operated pulley set-up.
-Easier to carry out replacement, alteration and maintenance. Demerits
-System is designed on a job-by-job basis
-More labour-intensive in the fixing and installation process
-Higher risk of leaking due to the existence of large amount of in-situ joints between mullion and panels.
-Involvement of large number of framing members coming from the mullion, transom or other framing parts that make the fixing at spot quite troublesome and inconsistent.
-Less fashionable for the design limited basically to monotonous grid without the elegance that other systems may achieve.
Unit System
Unit systems are composed of modulated panels that are fabricated in factory and delivered to site in one-piece for installation. The panels are fully provided with all the glazing and/or the spandrel panels, incorporated with the required insulation and other architectural features, thus requiring very limited second-fixed installation works on site. The panels are usually spanned in a floor-to-floor arrangement and may be designed in a number of standard/optional panels such as fully glazed, glazed with opaque panels, fully opaque in metal or stone slab, louvered panels, or other special modules like the corner or bayed units. In order to get the best benefit of using this system, units are often produced to an optimistic large size so as to minimize the number of units used.
This system has the following merits/demerits:
Merits
-Easy to install merely by securing the modulated panels onto the building exterior using fixing/connection devices which are usually very dimensionally flexible.
-Saving up a lot of manpower due to ease of installation.
-Higher performance units can be produced to meet stringent requirements due to better
control under factory environment.
-Preferably to be used in buildings with large walling area for the economy of scale in production as well as the elimination of countless assembly of minor components on site. Demerits
-It takes longer lead time to carry out the coordination, design and fabrication of the system/units.
-Require higher dimensional accuracy in the building structure for the fixing of the units.
-Lifting appliances may be required to assist the hoisting and installation of the large-sized walling units
-Difficult to carry out replacement or maintenance due to the interlocking nature of the modulated units.
Unit and mullion system
This is a combination of the stick system and the unit system and may be regarded as a compromise of the two. It is more suitable for use in medium-sized projects so as to balance the factors of lead time, ease of installation and economy of scale.
Panel system
A panel curtain wall system is similar to a unit system, the difference being that a panel system has homogeneous sheet or cast panel with few joints and may not have separate mullions. Unit systems are made up of smaller components fabricated together to form much complex panels that capable to perform heavier duties or other more specific requirements. However, due to the relative simplicity of the system, curtain wall of panel system design may not be able to fulfill the usual requirements most high-rise buildings required under Hong Kong’s environment. Its use is therefore more limited to certain kinds of buildings like those of standardized design for low-income classes or for buildings of industrial purposes. In this case, the panels can be constructed of sheet materials and manufactured in large quantity in very low cost.
Column-cover-and-spandrel system
Column-cover-and-spandrel system consists of column covers, which are usually made of alloyed aluminum, metal sheet or other laminated/fibre-reinforced sheet, and with glazing components and spandrel panels that fit between them. It resembles certain similarity to a unit-and-mullion system except that the structure of the building is exemplified by the column covers.
With the exception of the stick system and the unit system, other curtain wall systems are seldom used in Hong Kong.
Structural glazing system
The merit of using structural glazing system as external wall is to minimize the unglazed elements as much as possible, leaving glass panel almost as the only glazed surface on the wall. This can be done by providing larger mullion supports which span outward away frm the structural floor of a building. Special clamping devices such as a spider bracket can be used to hold the glazing panel in position. Structural sealant is used to seal up the gap between the glazing panels.
DESIGN PRINCIPLES FOR EXTERNAL WALL
A building enclosure may be broadly defined as a set of interconnecting elements which separate the outside from the inside. These elements would include exterior walls, a roof, other components such as windows and doors, and sometimes exposed floors. The function of a building enclosure is to control the penetration of snow, wind, rain and sun to the inside and to contain the desired indoor climate. The enclosure must meet many individual requirments but for the purpose of this paper they are limited to the following six:
control of air flow,
control of heat flow,
control over the entry of rain and snow,
control of sunlight and other forms of radiant energy,
control of water vapour diffusion,
accommodation of building movements.
The requirement for air tightness and consequently air leakage control is met by most curtain wall systems because the air barrier of the wall is inherent in the structural properties of glass and aluminum or steel tubes that comprise the system. The continuity of the air barrier (Figure 1) is achieved by the continuity of the glass panel through the air seal at the shoulder flanges of the tubular mullion, and through the aluminum section to the other flange surface. The air seal between the lower shoulder flange of the curtain wall mullion and the metal pan of the spandrel panel provides continuity of air tightness to the air barrier metal pan and on to the next mullion connection. Such assemblies are regularly tested using air pressure to determine the structural properties of the glass, metal, and seals and to determine the equivalent leakage area (ELA) that remains. In addition, the Architectural Aluminium Manufacturers Association imposes upon its members many other requirements including a specification that the system must not leak more than.30L/sperm2 of wall at a pressure difference equivalent to a 40 km/h wind.
Thermal Insulation (Control of heat flow)
The control of heat flow is generally achieved through the use of insulation. Although it is not apparent from the exterior, the curtain wall system uses considerable insulation usually behind spandrel glass or any opaque panels. Because of the materials used in the structure, i.e., glass and metal, which are highly conductive, the system must also contend with potential condensation on the interior surfaces. To curtail this effect, most curtain wall systems incorporate two distinct features: first, a sealed double glazed window or an insulated metal pan and second, a thermally broken mullion, usually with a PVC plastic insert and more recently, a foamed-in-place polyurethane connection. A sealed double glazed window unit can accommodate an indoor humidity up to about 35% at an outdoor temperature of -25 ° C with little condensation appearing on the glass. Similarly, the thermal break in the aluminum or steel mullion ensures that the surface
temperature of the structural mullion will remain well above the dew point temperature of the air for most building types, except for high humidity indoor environments such as in swimming pools or computer centers. The thermal break also ensures that the structural mullion is thermally stable, that is, not subject to extremes of expansion and contraction.
MAINTENANCE CONSIDERATION
Maintenance for curtain wall is a long-term consideration involving both the quality of design, control during construction and adequate maintenance throughout the life span. Once failure occurs in the curtain wall it will be very expensive to have the defects rectified and at the same time causing great disturbance to the building users. Below are some common problem sources where failures usually occur.
1.D esign failure – selection and appropriateness of the system, non-compliance to design and performance standards, imperfection in the jointing design and detailing, improper use of materials etc.
2.C onstruction and structural failure –wrong location or method of fixing, improper anchorage and connection provision (including failure in welding), failure in the walling components, unpredicted deflection or deformation appears in the background structure, poor supervision and workmanship.
3.A ging and deterioration –discolouring and surface damaging due to weather action; corrosion due to air pollution, acid rain, or electro-chemical effect to dissimilar metals; aging and hardening of the glazing compound or sealing gasket, deteriorating of the insulating materials that lead to further dampening of the walling materials/components, disfiguring or loosening of the fixing and connections, loosening or broken-off of the glazing or other fitting items.
Curtain wall systems should be inspected regularly after they have been installed in buildings. Proper maintenance and repair are essential to keep them in a safe condition. Inspection
arrangement should be made in particularly before and after typhoons. The below signs are recommended to observe closely during each inspection.
-Sign of distress and deterioration of the entire wall system,
-cracked, loose or missing glass panels,
-bulging, bowing, separation, delamination, rotation, displacement of panels,
-marks of water, staining and rust,
-damaged and missing parts, corrosion, loosening or other defects,
-extrusion, wrinkle, split, missing or other signs of deterioration of the sealing materials.
-moisture appears around or behind the curtain wall.
CONCLUSION
The application of curtain wall systems in super-highrise buildings is a big topic. Within the scope of this paper it can only cover a very little of the key issues. Having witnessed the evolution of using curtain wall in Hong Kong for the past 2 to 3 decades, a general trend, as summarized below, can be observed.
-Starting from low-cost, local-design and manufactured walling products in the early systems to the imported, deluxe, tailor-designed proprietary systems in recent years.
-Starting from simple requirements fulfilling just very basic functional needs of buildings to very specialized products or systems that can meet any stringent requirements as set by designer, engineers or environmental experts.
-The old systems were mainly stick systems due to more simple in design and production. Though labour-intensive, the relatively much cheaper labour cost at that time still made it worked acceptably. Contemporary systems are using mainly unit systems that make installation very easy and labour saving, though the design quality and coordination with other building activities are much more demanding.
-The old systems that have been used in the first and second generations often inherited with quite a lot of design imperfections and latent defects; while new systems are more reliable, some can be regarded as almost maintenance-free.
Traditional external walling methods using applied-onto products such as tile or spray-on coating are still dominating in Hong Kong. However, it is notable that the use of curtain wall is gaining its popularity quite rapidly among designers and developers due to its unreplaceable attractiveness as well as slim and fashionable appearance.
Further development and improvement in the use of curtain wall systems is an ongoing process in Hong Kong. The areas of improvement may be aiming at the development of more specific functioned, more reliable and long-life systems. Such targets may be achieved by the use of more advanced glass products, sealing compounds, gaskets or in the development of more sophisticated connecting systems; as well as the introduction of other additional functions that curtain wall may take up like the incorporation of photo-cell onto panels of wall, the providing of automatic/robotic machine in the system for external wall cleansing, or curtain wall capable to perform light show at night. Meanwhile, the continual improvement of workmanship and refinement of work detailing in particular to the areas directly in touch with the building structure or other building finishes, is a prime concern to the ensurance of a good curtain wall system, that sometimes project executives may easily overlooked.
中文译文：
超高层建筑幕墙系统的结构与性能
香港城市大学，建筑科学与技术部
Raymond WM Wong
引言
几十年来超高层建筑的建设在香港一直非常活跃。比如近期著名项目 50 层高的宏利大厦，62 层高的长江集团中心，80 层高的“中心”大厦，有 88 层高的国际金融中心，以及最近的一些超过 60 层楼高的住宅，这些项目无一例外都是采用幕墙作为他们的外部围护结构。
高层建筑如何采用薄壁外部围护结构一直是一个挑战设计师和建筑工的难题，特别是在成本、能源、水密性、安装性、尺寸方面、结构的稳定性、与其它建筑构件接口的搭配、维修等方面。笔者想利用香港的经验，来介绍一些当地薄壁幕墙系统设计和安装的实践和总结。
使用幕墙的香港建筑
自 1970 年始香港经济腾飞由传统的制造业进入了工业经济时代同时香港致力于把自己打造成一个世界知名的金融中心，高层建筑开始在香港的天际线涌现。在那时高层建筑主要集中在商业区如香港岛的中央和九龙半岛的尖沙咀一面。
第一代所谓的幕墙系统难以被描述为一个完整的系统。先锋系统通常是由当地建筑师设计外墙或墙面以及由当地制造商提供材料的设计。当时的通用系统大多数由铝部分构成有时并入大面积的石板掩盖其实心墙。由于其适应性强、成本低、易于设计和安装的性质非常地受欢迎。由于上世纪 70 年代香港经济越来越热更豪华的建筑开始出现。
开发商往往要求建筑外部围护系统在外观、材料、施工和保养担忧等方面具有更高的性能。
在这个阶段，由于相对缺乏经验，这些第二代幕墙系统（从 70 年代末到 80 年代中期）的表现仍然很难令人满意。存在防渗染色、变形、变质和拔节等快速老龄化问题。许多墙面往往由于维修的条件的限制维修几乎是不可能的。这些墙面的更换，不仅成本高，而且影响建设用户的正常使用而且严重降低了整个物业的属性值。
图 1 中环及香港尖沙咀九龙区
第三代幕墙系统的大致始于 80 年代末中期，因为当时香港在 1997 年交出她的主权回到中国前经历了经济高潮。高性能建筑在幕墙系统中的应用容纳体验对于完善这些系统贡献巨大。在整个期间，设计和生产团队以及制造商和工程配套队伍对当地情况的掌握变得越来越成熟，以前案件中出现的大部分问题都被有效地解决。这一代系统被用户广泛接受.
什么是幕墙
现代建筑越来越青睐于金属和玻璃幕墙系统。他们由全玻璃或金属板包裹容易识别的金属框构成幕墙系统。幕墙系统迅速发展了近二十年，特别是在气候控制性能等方面。由于经常下雨系统存在渗透问题，水渍补丁在内竖框表面的外侧形成。但是大多数的这些困难通过系统细节设计的改进最终被克服。在今天大多数的幕墙制造商可通过其高质量的生产线提供零部件，这些零部件可以被用来创建最佳的整体外墙系统。幕墙系统是一种挂在建筑结构的轻量级覆盖外墙，通常它可以提供多种外观，这些系统提供成品和半成品外观以适应结构变形、控制风力驱动的雨和空气泄漏、减少太阳辐射
的影响并提供了长期免维护的性能。虽然有些人可能认为金属幕墙是钢的但今天的大多数金属幕墙系统的构造采用轻质铝或其合金。
幕墙系统的常见类型
大面积外墙，除携带风载荷无其他附加荷载的釉面部分通常称为幕墙。传统幕墙是一个填充透明或不透明的面板的金属框架系统，但是需要提供玻璃、窗户来掩盖像柱、板和横梁或实心墙，甚至部分的结构。
有许多方法可以达到这个目的，这取决于许多因素例如设计和项目预算，布局和建筑结构的形状，以及其它建筑或结构要求。根据美国建筑制造商的标准，墙系统可分为 5 种类型，即在构件幕墙的系统、装置系统、装置和竖框的系统、面板系统、列盖-拱肩系统。然而，一些较新形式的幕墙系统由于引进高性能帧关节产品和高强度结构玻璃，是不能很容易地使用传统的观念来分类的，如大面积采用蜘蛛剪辑、低头竖框、衣架或电缆作为加强筋来支撑和连接的釉墙壁。
构件幕墙系统
幕墙构件幕墙系统是挂在建筑物的包层和外墙的系统结构。它是由各种部件包括钢或铝锚、竖框（垂直负载承受件）、导轨视力玻璃、窗间墙、铝绝缘和金属背衬盘组成。对于该系统的固定有各种各样的硬件部件如锚、连接器、支架、抽筋、设置块、角块、垫片和密封胶等。
该系统具有以下优点/缺点：
优点：成本低，可使用散装的标准原件；更短的设计和制造时间；
更加容易地适合建筑物的形状和形式；
形成竖框和背架的部分相对简单；
充填面板的设计非常灵活还可以形成各种组合；
使用不同的材料外观；
由于提供了拱肩面板（不透明部分）的设计，更多颜色的设计方案可以实现；安
装系统只需要建立一个像手动操作滑轮的简单工具；更容易进行更换，改造和维
修。
缺点：
系统设计上的作业，通过作业为基础；劳动密集型的固定和安装过程；由于大量原位之间的接缝的存在更高的漏水风险；
大量框架构件从竖框、梃未来或介入其他框架部分，使固定在现场相当麻烦和不一致。
图 2 - 用构件幕墙系统项目- 68 层高的信兴广场深圳（左）和网关在尖沙咀
翠。特写看看墙上的细节（中心图），信兴广场（上图）和网关（下）单元式系
统
单元式系统是由那些在制造工厂制造的调制板网进行一体式的安装。该小组提供所有的玻璃和拱肩板、所需的隔热及其他建筑特色，从而需要在第二工程现场进行固定安装。该面板可以设计成一些标准或可选版如全玻璃、釉面不透明板、金属或石板、完全不透明的百叶窗式面板等。本系统中为了得到最佳使用效益，单元式往往预留一个乐观的大尺寸，以减少使用单元式的数量。
该系统具有以下优点/缺点：
优点
调板只是固定到建筑外观易于安装，通常是非常灵活的尺寸固定或连接设备；
由于安装方便，节省了大量的人力；在工厂环境下由于更高的的要求控制使得
性能更高；生产大面积墙体规模经济建筑物可消除现场细琐的装配。
缺点
这些系统跟单元需要较长的时间来进行协调、设计和制造；建筑结构为单元式
的固定需要较高的尺寸精度；墙壁单元吊装和安装需要大型起重机械协助；
因其互锁性质难以进行更换或维护；
单元式和竖框系统这是构件幕墙系统和单元系统的组合，并且可被视为两者的相互制约。它更适合于中型项目使用，由于平衡的铅、时间等因素更加易于安装和规模生产。面板系统
一个板幕墙系统类似于一个单元系统，不同之处在于面板系统具有均匀的片或浇铸板形成的个关节，可能没有单独的窗棂。单元式系统由更小的组件装配在一起形成许多复合板能够执行更重的或其他更具体的要求。然而，由于该该系统的相对简单性，幕墙系统的板设计未必能够满足香港环境下所需的最高层建筑要求。其因此，使用仅限于某些种类的建筑的标准化原件于收入阶层或用于工业用途的建筑物。在这种情况下，该板可以是构成的片材，其生产成本更加低廉
列盖和-拱肩系统
列盖和-拱肩系统，其通常由合金化的铝，金属片或其他层压/纤维强化片组成的柱罩及玻璃组件和拱肩板填充其间。竖框系统不同的是建筑物的结构是与列盖相似的单元式。除了构件幕墙子系统和单元系统，其他幕墙系统很少在香港使用。结构性装配系统
使用结构玻璃系统作为外墙的优点是尽可能地减少无釉元素，仅留玻璃面板墙壁上的唯一上釉表面。这可以通过支撑竖框的外侧远离跨越做建筑物的结构层。特殊的夹紧装置，如蜘蛛支架可用于按住玻璃面板的位置。用于密封玻璃面板之间差距的结构密封胶。
图 4
外墙设计原则
建筑物外壳可以广义地定义为一组从内侧到外侧相互连接的单独的元素。这些要素包括外墙、屋顶、其他部件如门窗、有时露出地面。建筑围护的功能是控制的雪、风、雨和阳光渗透到里面以及调节所需的内气候，外壳须满足许多个性化需求，但对本文来说被限制在以下六个：
控制空气流控制热量
流控制雨雪的进入
控制阳光和其他形式的辐射能量
控制水蒸汽扩散
因此漏风控制的要求是由最满足帷幕墙系统建筑运动的气密性，因为壁的空气屏障的结构特性是玻璃以及铝或组成该系统的钢管。空气屏障的连续性（图 1）由通过空气密封的玻璃面板的肩部凸缘管状的竖框连续性来实现，并通过铝延伸到凸缘表面上。空气密幕墙竖框的下肩法兰及拱肩的金属盘面板将续性的空气阻挡提供更好的气密性。
结构需定检测玻璃、属性和封件并确定等效漏区（ELA）的属性仍然存在。此外，铝
外文出处： 《Exploiting Software How to Break Code》By Greg Hoglund, Gary McGraw Publisher : Addison Wesley Pub Date : February 17, 2004 ISBN : 0-201-78695-8 译文标题： JDBC接口技术 译文： JDBC是一种可用于执行SQL语句的JavaAPI（ApplicationProgrammingInterface应用程序设计接口）。它由一些Java语言编写的类和界面组成。JDBC为数据库应用开发人员、数据库前台工具开发人员提供了一种标准的应用程序设计接口，使开发人员可以用纯Java语言编写完整的数据库应用程序。 一、ODBC到JDBC的发展历程 说到JDBC，很容易让人联想到另一个十分熟悉的字眼“ODBC”。它们之间有没有联系呢？如果有，那么它们之间又是怎样的关系呢？ ODBC是OpenDatabaseConnectivity的英文简写。它是一种用来在相关或不相关的数据库管理系统（DBMS）中存取数据的，用C语言实现的，标准应用程序数据接口。通过ODBCAPI，应用程序可以存取保存在多种不同数据库管理系统（DBMS）中的数据，而不论每个DBMS使用了何种数据存储格式和编程接口。 1．ODBC的结构模型 ODBC的结构包括四个主要部分：应用程序接口、驱动器管理器、数据库驱动器和数据源。应用程序接口：屏蔽不同的ODBC数据库驱动器之间函数调用的差别，为用户提供统一的SQL编程接口。 驱动器管理器：为应用程序装载数据库驱动器。 数据库驱动器：实现ODBC的函数调用，提供对特定数据源的SQL请求。如果需要，数据库驱动器将修改应用程序的请求，使得请求符合相关的DBMS所支持的文法。 数据源：由用户想要存取的数据以及与它相关的操作系统、DBMS和用于访问DBMS的网络平台组成。 虽然ODBC驱动器管理器的主要目的是加载数据库驱动器，以便ODBC函数调用，但是数据库驱动器本身也执行ODBC函数调用，并与数据库相互配合。因此当应用系统发出调用与数据源进行连接时，数据库驱动器能管理通信协议。当建立起与数据源的连接时，数据库驱动器便能处理应用系统向DBMS发出的请求，对分析或发自数据源的设计进行必要的翻译，并将结果返回给应用系统。 2．JDBC的诞生 自从Java语言于1995年5月正式公布以来，Java风靡全球。出现大量的用java语言编写的程序，其中也包括数据库应用程序。由于没有一个Java语言的API，编程人员不得不在Java程序中加入C语言的ODBC函数调用。这就使很多Java的优秀特性无法充分发挥，比如平台无关性、面向对象特性等。随着越来越多的编程人员对Java语言的日益喜爱，越来越多的公司在Java程序开发上投入的精力日益增加，对java语言接口的访问数据库的API 的要求越来越强烈。也由于ODBC的有其不足之处，比如它并不容易使用，没有面向对象的特性等等，SUN公司决定开发一Java语言为接口的数据库应用程序开发接口。在JDK1．x 版本中，JDBC只是一个可选部件，到了JDK1．1公布时，SQL类包（也就是JDBCAPI）
forced concrete structure reinforced with an overviewRein Since the reform and opening up, with the national economy's rapid and sustained development of a reinforced concrete structure built, reinforced with the development of technology has been great. Therefore, to promote the use of advanced technology reinforced connecting to improve project quality and speed up the pace of construction, improve labor productivity, reduce costs, and is of great significance. Reinforced steel bars connecting technologies can be divided into two broad categories linking welding machinery and steel. There are six types of welding steel welding methods, and some apply to the prefabricated plant, and some apply to the construction site, some of both apply. There are three types of machinery commonly used reinforcement linking method primarily applicable to the construction site. Ways has its own characteristics and different application, and in the continuous development and improvement. In actual production, should be based on specific conditions of work, working environment and technical requirements, the choice of suitable methods to achieve the best overall efficiency. 1、steel mechanical link 1.1 radial squeeze link Will be a steel sleeve in two sets to the highly-reinforced Department with superhigh pressure hydraulic equipment (squeeze tongs) along steel sleeve radial squeeze steel casing, in squeezing out tongs squeeze pressure role of a steel sleeve plasticity deformation closely integrated with reinforced through reinforced steel sleeve and Wang Liang's Position will be two solid steel bars linked Characteristic: Connect intensity to be high, performance reliable, can bear high stress draw and pigeonhole the load and tired load repeatedly.
随着我国经济的发展,建筑行业已经朝着多元化方向发展,建筑行业在我国经济发展中起着非常重要的作用。而建筑工程管理工作直接关系到工程的质量、成本管理、人员的安全、企业的经营效益,甚至关系到企业的生死存亡,但是我国建筑工程管理在现阶段存在许多的不足:管理体制不健全。我国大部分的建筑工程为了节约人员开支,减少了建筑工程管理机构的人员数量和质量。管理制度深入性不足。建筑行业的相关管理制度都是由一些著名的建筑行业专家等共同研究制定的,但是在各建筑单位中就只是一张纸,他们也都只是为了应付上级的检查,并不能应用到建筑工程管理上。 在我国建筑工程管理工作中,难以全面确立我国建筑工程管理思路体系,主要是因为我国缺乏管理理论和经验。建立建筑工程管理思路体系是专业性较强的问题,其实施必须由资深的建筑学科专家和具有丰富工作经验的管理人员来组织,只有这样才能实现。国外建筑行业无论是技术还是理论都比较先进,因此我国在建筑工程管理思路体系的建立过程中,必须借鉴国外的先进理念,另外,还必须吸取先进的建筑工程管理方法,并对各方面的资料加以综合和整体。总之,要想确保我国建筑工程管理工作的有序进行,必须以健全的工程管理思路体系作为建筑工程总体管理水平提升的基本保障。加强施工质量管理,建立合理可行的质量保证体系,将工程的质量工作落到实处。工程施工企业要根据质量保证体系,形成行之有效的质量保证系统,树立质量方针,从而让其更加有指令性、系统性及可操作
性。要将人、材料和机械各个要素有效结合起来。 首先,人是质量控制的核心,要把人作为控制的推动力,充分调动人的积极性,树立工程质量第一的观念。其次,施工材料作为建筑产品的主体,对材料质量的控制是工程质量控制的关键。最后,工程施工的机械是进行施工机械化的主要标志,对现代化项目施工起到不可缺少的作用,它直接影响了施工项目的进度和质量,所以,选好用好工程机械设备非常重要。所以,应该根据工程项目的具体特点,综合考虑各种环境因素,实施有效的施工现场控制,为保证施工质量及安全创造良好的外部条件。 现阶段建筑工程管理越来越受到人们的重视,项目成本管理是工程管理不可或缺的内容。工程管理本质特征可以由项目成本管理体现出来。首先,建立项目成本管理责任制。项目管理人员的成本责任,不同于工作责任,工作责任完成不等于成本责任完成。在完成工作责任的同时,还应考虑成本责任的实施,进一步明确成本管理责任,使每个管理者都有成本管理意识,做到精打细算。其次,对施工队实行分包成本控制。项目部与施工队之间建立特定劳务合同关系,项目部有权对施工队的进度、质量、安全和现场管理标准进行监督管理,同时按合同支付劳务费用。再次,施工队成本的控制,由施工队自身管理,项目部不应该过多干预。 为了保证政府监督工作的有效性和权威性,应该提高监督队伍的整体素质。因此,加强建筑工程质量监督机构的质量管理的学习,从而使得监督队伍的业务素质得以提高。另外,质量监督手段也要不断进行完善,增加检测设备,使得监督工作具有较大科技的含量,实现监督工作的现代化。从建设市场的整体来看,市场运行的规则不够完善。执法不严,违法不究的现象常常会出现。工程质量受到危害在很大程度上都是由于建设市场的混乱所造成的。因此,政府必须建立健全的运行规则,保证这些规则能够真正落实处。
毕业设计（论文）外文文献翻译 文献、资料中文题目：软件开发概念和设计方法文献、资料英文题目： 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
外文资料原文 Software Development Concepts and Design Methodologies During the 1960s, ma inframes and higher level programming languages were applied to man y problems including human resource s yste ms,reservation s yste ms, and manufacturing s yste ms. Computers and software were seen as the cure all for man y bu siness issues were some times applied blindly. S yste ms sometimes failed to solve the problem for which the y were designed for man y reasons including: ?Inability to sufficiently understand complex problems ?Not sufficiently taking into account end-u ser needs, the organizational environ ment, and performance tradeoffs ?Inability to accurately estimate development time and operational costs ?Lack of framework for consistent and regular customer communications At this time, the concept of structured programming, top-down design, stepwise refinement，and modularity e merged. Structured programming is still the most dominant approach to software engineering and is still evo lving. These failures led to the concept of "software engineering" based upon the idea that an engineering-like discipl ine could be applied to software design and develop ment. Software design is a process where the software designer applies techniques and principles to produce a conceptual model that de scribes and defines a solution to a problem. In the beginning, this des ign process has not been well structured and the model does not alwa ys accurately represent the problem of software development. However,design methodologies have been evolving to accommo date changes in technolog y coupled with our increased understanding of development processes. Whereas early desig n methods addressed specific aspects of the
NET-BASED TASK MANAGEMENT SYSTEM Hector Garcia-Molina, Jeffrey D. Ullman, Jennifer Wisdom ABSTRACT In net-based collaborative design environment, design resources become more and more varied and complex. Besides com mon in formatio n man ageme nt systems, desig n resources can be orga ni zed in connection with desig n activities. A set of activities and resources linked by logic relations can form a task. A task has at least one objective and can be broken down into smaller ones. So a design project can be separated in to many subtasks formi ng a hierarchical structure. Task Management System (TMS) is designed to break down these tasks and assig n certa in resources to its task no des. As a result of decompositi on. al1 desig n resources and activities could be man aged via this system. KEY WORDS : Collaborative Design, Task Management System (TMS), Task Decompositi on, In formati on Man ageme nt System 1 Introduction Along with the rapid upgrade of request for adva need desig n methods, more and more desig n tool appeared to support new desig n methods and forms. Desig n in a web en vir onment with multi-part ners being invo Ived requires a more powerful and efficie nt man ageme nt system .Desig n part ners can be located everywhere over the n et with their own organizations. They could be mutually independent experts or teams of tens of employees. This article discussesa task man ageme nt system (TMS) which man ages desig n activities and resources by break ing dow n desig n objectives and re-orga nizing desig n resources in conn ecti on with the activities. Compari ng with com mon information management systems (IMS) like product data management system and docume nt man ageme nt system, TMS can man age the whole desig n process. It has two tiers which make it much more flexible in structure. The lower tier con sists of traditi onal com mon IMSS and the upper one fulfills logic activity management through controlling a tree-like structure, allocating design resources and
专业资料 学院： 专业：土木工程 姓名： 学号： 外文出处：Structural Systems to resist (用外文写) Lateral loads 附件：1.外文资料翻译译文；2.外文原文。
附件1：外文资料翻译译文 抗侧向荷载的结构体系 常用的结构体系 若已测出荷载量达数千万磅重，那么在高层建筑设计中就没有多少可以进行极其复杂的构思余地了。确实，较好的高层建筑普遍具有构思简单、表现明晰的特点。 这并不是说没有进行宏观构思的余地。实际上，正是因为有了这种宏观的构思，新奇的高层建筑体系才得以发展，可能更重要的是：几年以前才出现的一些新概念在今天的技术中已经变得平常了。 如果忽略一些与建筑材料密切相关的概念不谈，高层建筑里最为常用的结构体系便可分为如下几类： 1.抗弯矩框架。 2.支撑框架，包括偏心支撑框架。 3.剪力墙，包括钢板剪力墙。 4.筒中框架。 5.筒中筒结构。 6.核心交互结构。 7. 框格体系或束筒体系。 特别是由于最近趋向于更复杂的建筑形式，同时也需要增加刚度以抵抗几力和地震力，大多数高层建筑都具有由框架、支撑构架、剪力墙和相关体系相结合而构成的体系。而且，就较高的建筑物而言，大多数都是由交互式构件组成三维陈列。 将这些构件结合起来的方法正是高层建筑设计方法的本质。其结合方式需要在考虑环境、功能和费用后再发展，以便提供促使建筑发展达到新高度的有效结构。这并
不是说富于想象力的结构设计就能够创造出伟大建筑。正相反，有许多例优美的建筑仅得到结构工程师适当的支持就被创造出来了，然而，如果没有天赋甚厚的建筑师的创造力的指导，那么，得以发展的就只能是好的结构，并非是伟大的建筑。无论如何，要想创造出高层建筑真正非凡的设计，两者都需要最好的。 虽然在文献中通常可以见到有关这七种体系的全面性讨论，但是在这里还值得进一步讨论。设计方法的本质贯穿于整个讨论。设计方法的本质贯穿于整个讨论中。 抗弯矩框架 抗弯矩框架也许是低，中高度的建筑中常用的体系，它具有线性水平构件和垂直构件在接头处基本刚接之特点。这种框架用作独立的体系，或者和其他体系结合起来使用，以便提供所需要水平荷载抵抗力。对于较高的高层建筑，可能会发现该本系不宜作为独立体系，这是因为在侧向力的作用下难以调动足够的刚度。 我们可以利用STRESS，STRUDL 或者其他大量合适的计算机程序进行结构分析。所谓的门架法分析或悬臂法分析在当今的技术中无一席之地，由于柱梁节点固有柔性，并且由于初步设计应该力求突出体系的弱点，所以在初析中使用框架的中心距尺寸设计是司空惯的。当然，在设计的后期阶段，实际地评价结点的变形很有必要。 支撑框架 支撑框架实际上刚度比抗弯矩框架强，在高层建筑中也得到更广泛的应用。这种体系以其结点处铰接或则接的线性水平构件、垂直构件和斜撑构件而具特色，它通常与其他体系共同用于较高的建筑，并且作为一种独立的体系用在低、中高度的建筑中。
I / 11 本科毕业设计外文翻译 <2018届） 论文题目基于WEB 的J2EE 的信息系统的方法研究 作者姓名[单击此处输入姓名] 指导教师[单击此处输入姓名] 学科(专业 > 所在学院计算机科学与技术学院 提交日期[时间 ]
基于WEB的J2EE的信息系统的方法研究 摘要：本文介绍基于工程的Java开发框架背后的概念，并介绍它如何用于IT 工程开发。因为有许多相同设计和开发工作在不同的方式下重复，而且并不总是符合最佳实践，所以许多开发框架建立了。我们已经定义了共同关注的问题和应用模式，代表有效解决办法的工具。开发框架提供：<1）从用户界面到数据集成的应用程序开发堆栈；<2）一个架构，基本环境及他们的相关技术，这些技术用来使用其他一些框架。架构定义了一个开发方法，其目的是协助客户开发工程。 关键词：J2EE 框架WEB开发 一、引言 软件工具包用来进行复杂的空间动态系统的非线性分析越来越多地使用基于Web的网络平台，以实现他们的用户界面，科学分析，分布仿真结果和科学家之间的信息交流。对于许多应用系统基于Web访问的非线性分析模拟软件成为一个重要组成部分。网络硬件和软件方面的密集技术变革[1]提供了比过去更多的自由选择机会[2]。因此，WEB平台的合理选择和发展对整个地区的非线性分析及其众多的应用程序具有越来越重要的意义。现阶段的WEB发展的特点是出现了大量的开源框架。框架将Web开发提到一个更高的水平，使基本功能的重复使用成为可能和从而提高了开发的生产力。 在某些情况下，开源框架没有提供常见问题的一个解决方案。出于这个原因，开发在开源框架的基础上建立自己的工程发展框架。本文旨在描述是一个基于Java的框架，该框架利用了开源框架并有助于开发基于Web的应用。通过分析现有的开源框架，本文提出了新的架构，基本环境及他们用来提高和利用其他一些框架的相关技术。架构定义了自己开发方法，其目的是协助客户开发和事例工程。 应用程序设计应该关注在工程中的重复利用。即使有独特的功能要求，也
Commercial Buildings Abstract: A guide and general reference on electrical design for commercial buildings is provided. It covers load characteristics; voltage considerations; power sources and distribution apparatus; controllers; services, vaults, and electrical equipment rooms; wiring systems; systems protection and coordination; lighting; electric space conditioning; transportation; communication systems planning; facility automation; expansion, modernization, and rehabilitation; special requirements by occupancy; and electrical energy management. Although directed to the power oriented engineer with limited commercial building experience, it can be an aid to all engineers responsible for the electrical design of commercial buildings. This recommended practice is not intended to be a complete handbook; however, it can direct the engineer to texts, periodicals, and references for commercial buildings and act as a guide through the myriad of codes, standards, and practices published by the IEEE, other professional associations, and governmental bodies. Keywords: Commercial buildings, electric power systems, load characteristics 1. Introduction 1.1 Scope This recommended practice will probably be of greatest value to the power oriented engineer with limited commercial building experience. It can also be an aid to all engineers responsible for the electrical design of commercial buildings. However, it is not intended as a replacement for the many excellent engineering texts and handbooks commonly in use, nor is it detailed enough to be a design manual. It should be considered a guide and general reference on electrical design for commercial buildings. 1.2 Commercial Buildings The term “commercial, residential, and institutional buildings”as used in this chapter, encompasses all buildings other than industrial buildings and private dwellings. It includes office and apartment buildings, hotels, schools, and churches, marine, air, railway, and bus terminals, department stores, retail shops, governmental buildings, hospitals, nursing homes, mental and correctional institutions, theaters, sports arenas, and other buildings serving the public directly. Buildings, or parts of buildings, within industrial complexes, which are used as offices or medical facilities or for similar nonindustrial purposes, fall within the scope of this recommended practice. Today’s commercial buildings, because of their increasing size and complexity, have become more and more dependent upon adequate and reliable electric systems. One can better understand the complex nature of modern commercial buildings by examining the systems, equipment, and facilities listed in 1.2.1. 1.2.2 Electrical Design Elements In spite of the wide variety of commercial, residential, and institutional buildings, some electrical design elements are common to all. These elements, listed below, will be discussed generally in this section and in detail in the remaining sections of this recommended practice. The principal design elements considered in the design of the power, lighting, and auxiliary systems include: 1) Magnitudes, quality, characteristics, demand, and coincidence or diversity of loads and load factors 2) Service, distribution, and utilization voltages and voltage regulation 3) Flexibility and provisions for expansion
《文献检索》课程教学设计 目录 绪论：文献（信息）检索的意义及基础 (2) 项目一科技文献检索方法和图书馆的科学利用 (8) 项目二常见化学化工科技论文的写作 (11) 项目三美国化学文摘的使用 (14) 项目四专利文献的查询 (17) 项目五标准文献的查询 (20) 项目六计算机信息检索的应用 (23) 项目七信息检索策略综合应用训练 (26)
徐州工业职业技术学院教学设计（讲稿）
教学内容与设计 绪论：文献（信息）检索的意义及基础 自我介绍 提问一：你会检索吗？ 如果会，那么会用检索以下毕业专题的相关资料吗？ ?杜仲叶中绿原酸的提取分离 ?有机废水处理工艺设计 ?蚕丝蛋白制备工艺研究 ?铁矿石含铁量测定方法新工艺 ?基因工程干扰素生产工艺研究 提问的目的：突出检索技术直接是为毕业专题服务，这是一门技术。提问二：信息检索课是什么？ 学生如是说： 文献检索课程是井底之蛙的升降机，是雄鹰的翅膀，是横跨天堑的桥梁。 针对某一课题，通过电子检索查阅有关资料，才知道知识的浩瀚，才知道世界的宽广，才知道“山外青山，楼外楼”。 它是我在大学期间所学的最重要，最有用的课程之一，有了它，我们将会受益终生。教会我们一种方法，一种主动 了解外界，提高自己，放眼世界的方法。 检索不仅是我们学习的制胜法宝，更是一条贯穿我们生活的红线。正因为有了这门课的学习，现在大脑的检索意识 就比较强烈，越搜越快！前几天，问同学借自行车，他告 诉我车子大致地点，是永久牌，有车栏，略有一点蓝。到 了现场，脑海中一下就有了先找有栏的，再找蓝颜色的， 最后确定是不是永久的，很快就找到了。 我爱检索，就像爱自己的生命一样。 最后我想说，我们是幸运的！我们学到了一门真正有用的课，它对我的影响和帮助将是伴随我一身的。 提问三：借鉴与创新的关系？ 科学研究是“站在前人肩膀上”的事业，而创新又是科学研究的灵魂，即要求“前无古人”。 时间分配 2min 引导学生回答 8min 10min 通过往届学生对信息检索课的评价能够激起学生学习这门课的兴趣，也可以突出这门课对个人的作用。 10min 通过提问让学生
Section 3 Design philosophy, design method and earth pressures 3.1 Design philosophy 3.1.1 General The design of earth retaining structures requires consideration of the interaction between the ground and the structure. It requires the performance of two sets of calculations: 1）a set of equilibrium calculations to determine the overall proportions and the geometry of the structure necessary to achieve equilibrium under the relevant earth pressures and forces; 2）structural design calculations to determine the size and properties of thestructural sections necessary to resist the bending moments and shear forces determined from the equilibrium calculations. Both sets of calculations are carried out for specific design situations (see 3.2.2) in accordance with the principles of limit state design. The selected design situations should be sufficiently Severe and varied so as to encompass all reasonable conditions which can be foreseen during the period of construction and the life of the retaining wall. 3.1.2 Limit state design This code of practice adopts the philosophy of limit state design. This philosophy does not impose upon the designer any special requirements as to the manner in which the safety and stability of the retaining wall may be achieved, whether by overall factors of safety, or partial factors of safety, or by other measures. Limit states (see 1.3.13) are classified into: a) ultimate limit states (see 3.1.3); b) serviceability limit states (see 3.1.4). Typical ultimate limit states are depicted in figure 3. Rupture states which are reached before collapse occurs are, for simplicity, also classified and
PA VEMENT PROBLEMS CAUSED BY COLLAPSIBLE SUBGRADES By Sandra L. Houston,1 Associate Member, ASCE (Reviewed by the Highway Division) ABSTRACT: Problem subgrade materials consisting of collapsible soils are com- mon in arid environments, which have climatic conditions and depositional and weathering processes favorable to their formation. Included herein is a discussion of predictive techniques that use commonly available laboratory equipment and testing methods for obtaining reliable estimates of the volume change for these problem soils. A method for predicting relevant stresses and corresponding collapse strains for typical pavement subgrades is presented. Relatively simple methods of evaluating potential volume change, based on results of familiar laboratory tests, are used. INTRODUCTION When a soil is given free access to water, it may decrease in volume, increase in volume, or do nothing. A soil that increases in volume is called a swelling or expansive soil, and a soil that decreases in volume is called a collapsible soil. The amount of volume change that occurs depends on the soil type and structure, the initial soil density, the imposed stress state, and the degree and extent of wetting. Subgrade materials comprised of soils that change volume upon wetting have caused distress to highways since the be- ginning of the professional practice and have cost many millions of dollars in roadway repairs. The prediction of the volume changes that may occur in the field is the first step in making an economic decision for dealing with these problem subgrade materials. Each project will have different design considerations, economic con- straints, and risk factors that will have to be taken into account. However, with a reliable method for making volume change predictions, the best design relative to the subgrade soils becomes a matter of economic comparison, and a much more rational design approach may be made. For example, typical techniques for dealing with expansive clays include: (1) In situ treatments with substances such as lime, cement, or fly-ash; (2) seepage barriers and/ or drainage systems; or (3) a computing of the serviceability loss and a mod- ification of the design to "accept" the anticipated expansion. In order to make the most economical decision, the amount of volume change (especially non- uniform volume change) must be accurately estimated, and the degree of road roughness evaluated from these data. Similarly, alternative design techniques are available for any roadway problem. The emphasis here will be placed on presenting economical and simple methods for: (1) Determining whether the subgrade materials are collapsible; and (2) estimating the amount of volume change that is likely to occur in the 'Asst. Prof., Ctr. for Advanced Res. in Transp., Arizona State Univ., Tempe, AZ 85287. Note. Discussion open until April 1, 1989. To extend the closing date one month,