In the 20th century, bridge construction technology evolved and was fueled by the Industrial Revolution. At the turn of the century, steel bridges were riveted together, not bolted; concrete bridges were cast in place, not precast; and large bridge members were built from lacing bars and smaller sections, not rolled in one piece. Plastic had not yet been invented. Construction techniques such as post-tensioning, slurry walls, soil freezing, and reinforced earth walls had not yet been conceived. Surveying was performed mechanically since infrared, optical technology was still 75 years away. Bridge construction is changing as the new millennium begins. New construction techniques and new materials are emerging. There are also new issues facing the bridge building industry relative to the research needs associated with these new techniques and materials. LONG-SPAN BRIDGES Suspension Bridges While suspension bridge building was conducted at a modest pace throughout the 20th century, an unprecedented number of spans of remarkable record lengths were built in the Far East and Denmark. Both the Akashi Kaikyo Bridge in Japan and the Great Belt Bridge in Denmark were completed in 1998. The Akashi Kaikyo Bridge is the largest suspension bridge in the world, with a span of 1991 m, and the Great Belt Bridge is the second largest, with a span of 1624 m. While spans lengths have increased nearly fivefold during the course of this century, they may have reached their physical limits with today’s materials. Research will be necessary to develop the new, ultra-high-strength steel wire or carbon fiber wire required to build the longer main suspension cables that will make it possible to increase span lengths to beyond 2000 m. As we enter the new millennium, rehabilitation and ongoing maintenance of the existing suspension bridges must continue as well. Recent rehabilitation measures for the main cables and suspension systems of these bridges have uncovered degradation through corrosion and hydrogen embrittlement. Research is needed to determine the remaining useful service life of suspension bridge cables and what measures can be taken to slow or halt the degradation process. Transportation in the New Millennium 2 Other components of long-span bridges, existing and new, are being revolutionized as technology moves forward. Advances in deck technology are producing stronger, lighter decks. Orthotropic and exodermic decks are becoming increasingly popular on long-span structures as a means of reducing dead load. Bearings, joint systems, and seismic retrofitting components are becoming increasingly efficient as more large-scale testing facilities are built.在20世纪,桥梁施工技术,是由进化而来的 工业革命。随着新世纪的到来,钢桥受到铆接在一起,而不是 螺栓、混凝土桥梁被扔在的地方,不是预制、大型桥梁成员 从系酒吧和小的部分,不卷在一块。塑料尚未 发明了。制作等施工工艺、浆墙、土壤冻结, 加筋土墙尚未怀了孕。测量进行机械 自从红外、光学技术仍然是75年。 大桥建设是新千年开始转变。新建筑 技术和新材料正在浮出水面。也有新的解决面临的桥 建筑行业的相关研究的需要,这些新技术 材料。 大跨度桥梁 悬挂的桥梁 虽然悬索桥建设进行了整个20速度不快 世纪,前所未有的跨越了卓越的长度是建在记录 远东和丹麦。双方在日本明石海峡大桥正式通车,伟大的带桥 在丹麦是在一九九八年完成。这个明石海峡大桥正式通车是世界上最大的悬架 在这个世界上,与桥梁的m,1991年是中国的第二大带桥, 用一段1624)。 虽然已经增加了近5倍长度的跨世纪的过程中, 他们已经达到了他们的物理极限与今天的材料。研究将 必须发展新的、ultra-high-strength钢丝、碳纤维丝要求 建立了悬索,将不再主要可能增加到跨度的长度 超出2000米。 当我们进入新千年、康复和持续的维护现有的 悬索桥必须继续。最近的戒毒措施为主要 电缆悬架系统与这些桥梁发现退化 氢脆腐蚀,。研究还剩下的 寿命悬索桥电缆和什么措施可以减缓或 停止退化的过程。 在新千年的运输 其他组件的大跨度桥梁,现有的和新的,正在发生了革命性的变化 技术的进步。提出了在甲板上技术生产强的,更轻的 甲板。正交各向异性和exodermic牌是大跨度越来越受欢迎 作为一种手段,降低结构自重荷载。轴承、联合系统和抗震能力 越来越多的有效成分是更大规模的测试设备 建造。 50分!!~~谢谢 参考资料:我的大脑
Along with the our country economic development rapid development, the lives of the people level unceasing enhancement, the city uses to be day by day anxious, urges the building to face the direction is developing. This kind of high level civil construction repair needed materials and the way also more hasten the diversification, and along with uses electricity the load and coal gas consumption quantity enlarging, proposed to the fire auto-alarm system design is higher, a stricter request. In order to guarantee the people life and property the security, the fire auto-alarm system design has become in the high level civil construction design one of most important design contents. Presently based on the author fire of auto-alarm system design overseeing work in the high level civil building experience, proposed in present national related standard and standard unclear true detail shallow opinion, by for the colleagues to discuss and to point out , design basis The fire auto-alarm system design is a specialized very strong technology work, at the same time also has the very strong policy-type. Therefore, first should be clear about the following design basis: 1st, must grasp the architectural design fire protection standard, the system design standard, the equipment manufacture standard, the installment construction approval standard and the administration laws and regulations and so on five big aspects fire laws and regulations, and in practical understanding present country related standard and standard positive word: "Must", "be supposed", "to be suitable", "may" and the reverse side word: "Strictly prohibits", "should not", "not have", "not to be suitable" the , must aim at high level civil building function, use and the protection object fire protection rank, earnestly carries out the present national related standard and the standard, earnestly treats the public security fire prevention surveillance department the examination and approval , fire auto-alarm system equipment establishmentFire detector establishmentOpens wide either the seal or the stair hall should alone divide the search coverage, and each 2 ~ 3 establish a fire first room (including guards against in front of smoke stair hall in front of room, fire elevator room, fire elevator with guards against the front room which smoke stair hall comes in handy) and the aisle should distinguish alone to divide the search coverage, specially front the room and the lift well, the scattered stair hall and the aisle are interlinked, has time the fire haze to be easier to gather or to flow, is the personnel disperses which saves goal with the fire prevention, therefore should install the fire detector. Regarding common elevator in front of room although is not the personnel disperses , but this front room and the lift well are interlinked, has time the fire haze to be also easy to gather or to flow, suitably alone divides the search coverage and installs the fire detector. The electric cable shaft therefore is easy to form pulls out the smoke inflammation the channel; Has when the fire the fire intensity not easily extends along the electric cable burns, for this, "the high level civil construction design fire protection standard" and "the civil construction electricity design standard" separately proposes the detailed specific stipulation in the construction and in the electric wire or on the electric cable shaping. But considered implements specifically the difficulty and the present situation, the electric cable shaft installs the fire detector is extremely essential, and coordinates the shaft the fire protection separation request, each 2 ~ 3 or each level elevator machine room should install the fire detector, its elevator is the important vertical transportation vehicle; Its two elevator machine room has has the fire risk; Its three lift well existence essential opens the hole, like the level gate opens between the hole, the air vent, the between permanence opens the hole with the elevator machine room or the pulley and so on; Its four when has the fire, the lift well often becomes the fire intensity spread the channel, is easy to threaten the elevator machine room the facility. Therefore, the elevator machine room establishes the fire detector is necessary, crown of also suitable establishment fire detector lift , the manual fire reports to the police the button establishment(Including guards against in front of smoke stair hall in view of various floors front room in front of room, fire elevator room, fire elevator with guards against which smoke stair hall to come in handy the front room) is has when the fire the personnel to disperse which saves goal with fire prevention, should report to the police the button first choice spot as the establishment manual fire. In addition, the room also should establish the manual fire to the common elevator in front of to report to the police the the public active place (including hall, hall, dining room, multi-purpose hall and so on) and the main thoroughfare and so on place, the personnel very is all centralized, and mainly disperses the channel. Therefore should report to the police the button in these public active places main access establishment manual fires; The manual fire establishes which in the main thoroughfare reports to the police the button to guarantee "to a manual fire which most is close to reports to the police the button distance from a fire protection district any position not to be supposed to be bigger than 30 meters".3rd, the fire emergency broadcasts the speaker the establishmentThe aisle, the hall, the dining room and so on the public place personnel very are all centralized, and mainly disperses the channel. Therefore should press in these public places "to a recent speaker distance is not bigger than 25 meters from a fire protection district any spot" and "in the aisle last should not be bigger than meters the speaker to the aisle terminal distance" the establishment fire emergency to broadcast the speaker; Next also should establish the fire in the public bathroom place emergency to broadcast the first room (including guards against in front of smoke stair hall in front of room, fire elevator room, fire elevator with guards against which smoke stair hall to come in handy the front room) is has when the fire the personnel to disperse which saves goal with fire prevention, also has the fire door separation and the sounds of people is confused and noisy, therefore should establish the fire emergency to broadcast the speaker. In front of the common elevator the room also should establish the fire emergency to broadcast the speaker. Disperses the stair hall also is has when the fire the personnel to disperse which saves goal with the fire prevention, also the sounds of people are confused and noisy, therefore should establish the fire emergency to broadcast the speaker, by favors the fire emergency broadcast to disperse the , fire alarm installment establishmentThe establishment fire emergency broadcast fire auto-alarm system, the author thought also should install the fire alarm installment, but its control procedure should be: The alarm apparatus should confirm after the fire, uses manual or the automatic control mode unification to the fire correlation region transmission warning, stops the alarm apparatus work in the stipulation time, the rapid linkage fire emergency broadcast and broadcasts to the people disperses the fire alarm installment establishment position, the author thought should report to the police the button position with the manual fire to be same, its wall surface installment should for be apart from the ground meters highly5th, fire special use telephone establishmentInstalls the fire special use telephone extension telephone, should be located the engine room which related also some people is on duty frequently with the fire linkage control (including fire water plant, spare electricity generation engine room, matches substation, mainly ventilates with air conditioning engine room, discharges fume engine room, fire prevention elevator machine room and other), the fire fighting control system operates the equipment place or the control room, the fire duty officers observation room, the security manages spot and so on public room. Sedan of theater box the fire elevator and in the ordinary elevator all should suppose the special use telephone, requests the elevator machine room and the elevator sedan theater box, the elevator machine room and the fire control room, the elevator sedan theater box and the fire control room and so on three compositions is reliable to speaks the correspondence telephone system. Usually in fire control room; The establishment elevator monitoring demonstration plate (including position indicator, direction indicating lamp, to speaks correspondence telephone, trouble lamp and so on), in order to carries on the necessity to the elevator running status which in the surveillance and the emergency case equipped with the manual fire to report to the police position and so on button, fire hydrant button also should install the fire special use telephone , fire linkage control 1st, the fire linkage control should include the control fire pump to open, to stop, also should demonstrate opens pumps the button the position and the fire pump work and the malfunction. When the fire hydrant is equipped with the fire hydrant button, its electric installation work spot also should demonstrate the fire pump the working mode active status (namely establishment fire pump work indicating lamp). 2nd, the fire linkage control should include the control spraying of water and the water atomization fire fighting system opens, stops, also should demonstrate the fire pump the work and the malfunction and the fluent display, reports to the police the valve, the safety signal valve working mode active status. In addition, to the basin, the water tank water level also should carry on the demonstration monitor; In order to prevent the overhaul signal valve is shut down, the author thought should use the belt electric signal the control signal valve by to demonstrate it opens the condition. 3rd, the fire linkage control other controls and the demonstration function, should carry out the present national related standard and the standard specific , fire auto-alarm system wiringIn order to prevent the fire occurs when the fire control, the correspondence and the warning line severance, causes the fire fighting work to be unable to carry on, creates the bigger economic loss; Also for the suppression electronmagetic interference (for example transformer, electric motor, electric cable and so on) the influence which produces to the fire auto-alarm system. The fire auto-alarm system transmission line and the fire control, the correspondence and the warning line should use the being flame-resistant electric cable, and should use the metal tube or the enclosed metal trunking protection. The fire manual positive governing installment line should use the fireproof electric cable, its electric cable also should use the metal tube or the enclosed metal trunking protection. Uses Ming Fushi, should takes the fire protection protective measures on the metal tube or the enclosed metal , concluding remarkThe author rests on the concrete project to implement the experience, elaborated the design basis, fire auto-alarm design actual problem and so on system equipment establishment, fire linkage control and its wiring pulls out some shallow opinions, its goal is enhances the fire auto-alarm system the design quality, discovered early and the notification fire, prevented and reduces the fire to harm, by protects the person and the property safety.随着我国经济发展快速发展,人民生活的水平不断提高,城市使用是每天着急,敦促建设面临着发展的方向。这种高层次的民间建筑维修所需的材料和方式也更加多样化加快,而且随着使用电力负荷和煤气消费量扩大,提议消防自动报警系统设计较高,更严格的要求。为了保证人民生命和财产的安全,消防自动报警系统的设计已经成为在高级别民间建筑设计的一个最重要的设计内容。目前的基础上撰文火灾自动报警系统设计监督工作的高层次的民间建设的经验,建议在目前国家相关标准和标准不清楚真正详细浅见解,为同事们的讨论,并指出错误。 首先,设计依据 火灾自动报警系统的设计是一家专业非常强的技术工作,同时还具有很强的政策性。因此,首先应明确以下设计依据: 第一,必须紧紧抓住的建筑设计防火标准,该系统的设计标准,标准的设备制造,安装施工审批标准和管理的法律和规章等五大方面的消防法律法规,并在实际了解国家有关本标准和标准积极字: “必须” , “必须假定” , “不适合” , “可能”和反面词: “严格禁止” , “不应该” , “没有” , “不适合“的含义。 第二,必须着眼于高层次的民间建筑的功能,利用和保护对象的防火等级,认真开展本标准和国家有关标准,认真对待公安防火监督部门的审批意见。 其次,火灾自动报警系统设备的建立 建立火灾探测器 要么全打开的印章或楼梯大厅应单独划分搜索范围,每个2 〜 3建立火灾探测器。 第一个房间(包括防前面的烟雾大厅楼梯前室,消防电梯间,消防电梯防前面房间烟雾楼梯大会堂来用场)和过道应区分单独划分搜索范围,特别是前面的房间,以及电梯,分散楼梯大厅和走道都是相互关联的,有时间的火灾烟雾比较容易收集或流动,是人员分散保存目标与防火,因此,应该安装火警探测器。关于共同电梯前室虽然不是人员分散,而且这方面的空间和良好的电梯是相互关联的,有时间的火灾烟雾也很容易被收集或流动,适当地划分为单独的搜索覆盖面和安装消防探测器。 电缆轴因此很容易形成掏出烟炎症渠道,拥有火灾时的火强度不容易延伸沿电缆燃烧,为此, “高级别民间建筑设计防火标准”和“民用建筑电气设计标准“分别提出了详细具体的规定,在建筑和在电线或电缆塑造。但认为具体实施的难度和目前的情况下,电缆竖井安装了火灾探测器是非常必要的,坐标轴的防火分隔要求,每2 〜 3或每一级安装。 电梯机房应安装火灾探测器,它的电梯是重要的垂直交通工具,其两个电梯机房已具有火灾危险性,其存在的三个基本解除以及打开洞,像打开闸门的水平之间的球洞,在气孔,持久的关系打开了洞与电梯机房或滑轮等,其时,有四个火,升降机以及往往成为火灾强度传播渠道,很容易危及电梯机房设施。因此,电梯机房建立了火灾探测器是必要的,也适用于皇冠建立火灾探测器举井。 2 ,手动火警报警按钮建立 (包括防前面的烟雾楼梯大厅鉴于各层前房间前面的房间,消防电梯间,消防电梯防这些烟雾楼梯大会堂派上用场前室)是有火灾时人员驱散节省目标,防火,应立即向警方举报的按钮,首选地点设立手动火警。此外,该室也应建立防火手册的共同电梯前,向警方报案的按钮。 在公共活动场所(包括会堂,礼堂,餐厅,多功能厅等)和主要通道等场所,是所有工作人员非常集中,主要是分散的渠道。因此,应立即向警方举报的按钮,在这些公共活动场所主要通道设立手册火灾;该手册规定的火灾中的主要通道报警按钮,以保证“ ,以手动火警最接近报警按钮距离防火区的任何位置不应该超过30米。 “ 第三,消防紧急广播喇叭建立 走道,大厅,餐厅等公共场所的工作人员都非常集中,主要是分散的渠道。因此,应该按这些公共场所的“最近的一项发言距离不超过25米的防火保护区的任何位置”和“在走道上不应大于十二点五米扬声器的过道末端距离”建立消防应急广播喇叭;下一步还应当建立消防在公共浴室的地方紧急广播喇叭。 第一个房间(包括防前面的烟雾大厅楼梯前室,消防电梯间,消防电梯防这些烟雾楼梯大会堂派上用场前室)是有火灾时的人员驱散节省目标与防火,也有分离和防火门的声音,人民的混乱和嘈杂,因此,应建立消防应急广播喇叭。在前面的共同电梯房也应建立消防应急广播喇叭。分散大厅楼梯也已经火灾时的人员驱散节省目标与防火,也是人民的声音和嘈杂的混淆,因此应建立消防应急广播喇叭,由主张消防紧急广播驱散指令。 第四,建立火灾报警装置 建立消防应急广播火灾自动报警系统,笔者认为还应该安装消防报警装置,但它的控制程序应该是:该报警器应确认火灾后,利用手动或自动控制模式统一消防相关区域传输预警,报警器停止工作时间的规定,迅速联系消防应急广播和电视节目,并且分散了人们的指示。 火警警报装置建立的立场,笔者认为应该向警方报案的按钮位置的手动火警是相同的,它的墙面安装应为距地面米高度 第五,消防专用电话设立 安装消防专用电话分机电话,应设机房其中也涉及一些人是在工作地点经常与消防联动控制(包括消防给水设备,备件发电机房,火柴变电站,主要ventilates空调引擎室,排放烟气轮机室,防火电梯机房及其他) ,消防控制系统的经营场所或设备的控制室,消防责任人员观察室,现场的安全管理等公共空间。轿车的影院中消防电梯和普通电梯应假设所有使用的特殊电话,请电梯机房和电梯轿车影院中,电梯机房及消防控制室,电梯轿车影院方块和消防控制室等三个成分是可靠的讲通信电话系统。通常在消防控制室;建立电梯监测演示板(包括位置指示器,显示方向灯,以讲信函电话,麻烦灯等) ,以进行必要的电梯在运行状态的监视和紧急情况下的控制。 配备了手动火警报警位置等按钮,消火栓按钮,还应该安装消防专用电话插座。 第三,消防联动控制 第一,消防联动控制应包括控制消防泵开启,停止,也应表现出的按钮,打开泵的位置和消防泵的工作和故障。当消火栓设有消火栓按钮时,其电气安装工程现场也应表现出的消防泵的工作模式有效状态(即建立消防泵工作表明灯) 。 第二,消防联动控制应包括控制喷洒水和水雾化灭火系统打开,停止,也应表现出的消防泵的工作和故障和流利显示,报警阀,安全信号阀工作模式积极的地位。此外,该盆地,水箱水位也应进行示范监测;为了防止检修信号阀关闭,作者认为应该使用带电信号控制信号阀证明它打开条件。 第三,消防联动控制其他控制和示范作用,应进行本标准和国家有关标准的具体规定。 第四,火灾自动报警系统布线 为了防止火灾发生时,消防控制,通信和警戒线遣散,使灭火工作无法进行,造成了更大的经济损失,也为抑制electronmagetic干扰(例如变压器,电电机,电缆等)的影响而产生的火灾自动报警系统。火灾自动报警系统的输电线路和消防控制,通信和预警线应使用被阻燃电缆,并应使用金属管或封闭式金属线槽保护。消防手册积极理事分期付款行应使用防火电缆,其电缆也应使用金属管或封闭式金属线槽保护。使用明复,应采取防火保护措施的金属管或封闭金属 ,结论备注 作者取决于具体的项目实施经验,阐述了设计依据,火灾自动报警设计和实际问题,以便建立系统设备,消防联动控制及其接线拿出一些肤浅的意见,其目的是增强了火灾自动报警系统的设计质量,早期发现,并通知消防,预防和减少火灾危害,通过保护个人和财产安全。
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