建筑 给排水 外文翻译 英文文献 多层住宅建筑给排水设计的几个问题

多层住宅建筑给排水设计的几个问题摘要：本文就多层住所修建给排水描绘中给水管材的选用，管道的敷设办法，水表出户设置，家用热水器的设置及空调冷凝水排放等疑问进行讨论，并提出一些详细观点。

关键字：多层住所给水管材管道敷设水表太阳能热水器多层住所以其配套设备简略，造价低，物业办理便利等特色，很受中小城市房地产开发商和广阔居民的欢送。

怎么按2000年小康住所科技产业工程寓居区计划描绘导则的需求，进步住所的描绘水平，为每个住户营建出一个舒服的日子空间，是每个描绘人员的职责所在。

作为住所的心脏――厨房、清洗间，是功用杂乱，清洗、安全和舒服度需求高，营建冗杂，技能需求高的空间。

因而，描绘人员有必要以全体描绘的观念和办法，归纳思考厨房、清洗间给排水管道和设备的装置等。

下面就多层住所给排水描绘中给水管材的选用、管道的敷设、水表出户设置、家用热水器的设置和空调冷凝水排放等疑问与同行们一同讨论。

（一）给水管材选用疑问传统的给水管材通常选用镀锌钢管，因为镀锌钢管易锈蚀，运用寿命短，用于运送日子用水不能满意水质清洗标准等缺陷，建设部正大力推行塑料给水管的运用。

许多地市已明文规定：制止描绘运用镀锌钢管，推行运用塑料给水管。

塑料给水管与金属管道比拟，具有重量轻，耐压强度好，运送液体阻力小，耐化学腐蚀功用强，装置便利，省钢节能，运用寿命长等长处。

给水用塑料管道首要有：硬聚氯乙烯（PVC －U）、高密度聚乙烯（HDPE）、交联聚乙烯（PEX）、改性聚丙烯（PP－R ，PP－C）、聚丁烯（PB）、铝塑复合管（PE－AL－PE，PEX－AL－PEX）和钢塑复合管等。

下表是几种修建给水管材功用的比拟。

管材功用长处缺陷长期运用温度短期运用温度硬聚氯乙烯管（PVC－U）抗腐蚀能力强，质地坚固，施工简洁有UPVC单体和添加剂渗出，管接头粘合技能需求高，固化时间长≤400C――改性聚丙烯（EN-US）PP －R，PP－C）耐温功用好，抗蠕变功用好，施工简洁只有用金属管件衔接；水流部分水头丢失大，不能收回重复运用900C950C铝塑复合管（PEX－AL－PEX）耐温功用好，保温功用好（EN-US）在平等压力和介质温度的条件下，管壁最厚，选用热熔衔接，需用专门衔接东西≤600C≤900C铝塑复合管（PE－AL－PE）易曲折成形，彻底消防氧浸透，线膨胀系数小，施工简洁管壁厚薄不均匀，管路衔接选用铜管件，水流部分水头丢失大≤400C――注：1）长期运用温度系指管道在此温度规模内运用寿命达30～50年2）短期运用温度系指管道在此温度规模运用寿命达10～20年管材的挑选是经济技能的比拟进程，技能上应从压力、温度、运用环境、装置办法等方面进行思考，一起联系业主的需求和住所的层次，进行经济技能归纳思考后断定。

建筑给排水英文文章一、IntroductionIn the field of architecture, plumbing systems play a crucial role in providing clean water and removing waste from a building. Effective and efficient building plumbing systems are essential for the health and safety of occupants. This article will explore the various aspects of building plumbing systems, including design principles, materials used, installation methods, and maintenance requirements.二、Design PrinciplesA well-designed plumbing system in a building relies on several key principles:1. Water Supply DesignThe design of a water supply system involves determining the source of water, calculating the required flow rate, and sizing the pipes accordingly. Factors such as building size, occupancy, and water demand must be considered. Additionally, backflow prevention devices are installed to prevent contamination of the water supply.2. Drainage System DesignThe drainage system design focuses on removing wastewater from the building and ensuring proper disposal. Gravity is commonly used to move wastewater through a series of pipes and drains. Proper slope, pipe diameter, and venting are important considerations to prevent blockages, odors, and sewer gas leaks.3. Fixture LayoutThe layout of plumbing fixtures, such as sinks, toilets, and showers, should be carefully planned to optimize water usage, convenience, andaccessibility. Adequate space and accessibility for maintenance should be considered during the design phase.三、Materials UsedVarious materials are used in the construction of plumbing systems. The choice of materials depends on factors such as the type of water supply, budget, and local regulations. Common materials used include:1. PipesPipes are typically made of materials such as copper, galvanized steel, PVC (polyvinyl chloride), and PEX (cross-linked polyethylene). Each material has its advantages and disadvantages, such as durability, cost, ease of installation, and resistance to corrosion.2. Fittings and ValvesFittings and valves connect and control the flow of water within the plumbing system. They are available in materials like brass, copper, and plastic. The choice of fittings and valves depends on the specific requirements of the system and its intended use.四、Installation MethodsProper installation of plumbing systems is crucial to ensure their functionality and longevity. Different installation methods are used depending on the building structure and plumbing system design. Some common installation methods include:1. Traditional Open-Cut MethodThis method involves excavating trenches for the placement of pipes. It allows for easy access and repair but can be time-consuming and disruptive, especially in existing buildings.2. Trenchless TechnologyTrenchless technology, such as pipe bursting and pipe lining, is gaining popularity due to its minimal disruption and cost-effectiveness. It involves using specialized equipment to repair or replace pipes without the need for extensive excavation.五、Maintenance RequirementsRegular maintenance is essential to keep building plumbing systems in optimal condition. Neglecting maintenance can lead to leaks, blockages, and water damage. Some important maintenance requirements include:1. Regular InspectionsPeriodic inspections of the plumbing system can help identify any potential issues before they escalate into costly repairs. Inspections should include checking for leaks, proper drainage flow, and functioning of valves and fixtures.2. Clearing BlockagesBlockages in drains and pipes should be promptly cleared to prevent backups and plumbing system failures. This may involve using mechanical tools or chemicals, depending on the nature of the blockage.3. Water Heater MaintenanceWater heaters should be inspected and serviced regularly to ensure efficient and safe operation. This includes checking for leaks, sediment buildup, and testing the pressure relief valve.六、ConclusionBuilding plumbing systems are vital for the functionality and comfort of a building. Proper design, choice of materials, installation methods, and regular maintenance are key factors in ensuring the performance and longevity of these systems. By following the principles discussed inthis article, architects, engineers, and building owners can createreliable and efficient plumbing systems that meet the needs of occupants while adhering to relevant regulations.。

Discussion on building water supply and drainage construction of commonproblems and Solutions浅谈建筑给排水施工中的常见问题及解决孙峰Abstract:Building water supply and drainage construction quality directly affects the building use function. In this paper, combined with the supervision of water supply and drainage engineering practice, for building water supply and drainage of common problems in construction were summarized and analyzed.Key words: building water supply and drainage construction qualityOur country national economy actual strength increases ceaselessly, construction industry develops rapidly, and constantly improve the level of overall construction of buildings. Construction equipment perfection degree and design level is the embodiment of building construction quality and an important symbol of modernization level, inside of the building water supply and drainage engineering is an important part of construction equipment, its technical level and advanced directly affects the using function of building, and people life, health, the environment, security. With the improvement of people's living standard, people in addition to the building safety, durability and economy have certain requirements, at the same time on the construction of the comfort, use requirements are also more attention, especially for the residential building energy saving and new energy utilization, Chuwei technology, pipeline technology, environment and security technology etc have higher requirements, these requirements in addition to the design and materials, equipment selection, construction greatly need assurance of installation quality. The quality of construction quality, directly affects the normal operation of the building water supply and drainage system. China's economic construction and development, various types of residential lots, building water supply and drainage technology of rapid development. However, with the increase of water supply and drainage engineering, also appeared some problems needed to be paid attention to, if not handled properly, will give householder brings a lot of unnecessary trouble. Therefore, the study on how to avoid water supply and drainage construction problems easy to occur is verynecessary. In the actual construction of water supply and drainage engineering construction, except in the raw materials and so on the objective factor to control the quality of water supply and sewerage works, improve employees' professional level, in strict accordance with the rules and regulations, standard operation, can be less problems, control of water supply and drainage project construction quality. Due to the level of management of construction enterprises, construction of personnel quality, building water supply and drainage construction quality is put in very big difference. Here in the construction process should pay attention to the problem is discussed:1 Living water supply systemAt present construction is widely used in aluminum-plastic composite pipe and polypropylene random copolymerization polypropylene ( PP - R ) tube. Plastic pipe has the advantages of light weight, no rust, scale, manufacturing, low energy consumption, smooth inner wall, hydraulic condition is superior, quality health, no pipeline two pollution, low labor intensity, saving installation of comprehensive construction cost advantages. PP - R water pipe connecting method is the use of fusion welding, aluminum-plastic composite pipe made of copper connection. The former applies for surface mounting, the latter applies to the dark. But there are some problems in the construction of which need special attention.(1) In the vertical tube lead-out branch tube three through parts arranged at the supporting point, the intermediate support is still in accordance with the provisions set. In the installation of pipelines should be considered in the pipeline of linear expansion, PP - R plastic water supply pipe expansion coefficient than the metal tube, wall concealed piping due to wall finally with cement mortar cement mortar filling pipeline, friction and plastic pipe special good creep effect, so that the shaft extension into radial change, therefore, block wall pipeline, can be considered linear expansion. For the pipeline, when the distance is longer, should consider adopting a telescopic device and the angle of natural compensation(2) Outdoor installed plastic water supply pipe must have reliable shading or heat preservation measures, through the pipeline settlement joints for compensating treatment. Because plastic pipe anti aging performance have certain limit, when exposed to install, long-term sun exposure can accelerate aging of plastic material, it should be considered to take effective shading or insulation measures. In addition the pipeline settlement joints shall be taken compensation measures, or easy to make pipeline rupture, appeared the phenomenonof water leakage(3)In the kitchen, Wei bovine apparatus for concentrating bathrooms, should adopt the water separator. Using plastic tube as a cold, hot water pipe concealed in floor slab of concrete in plastic pipe, due to the linear expansion coefficient of metal pipe to relatively large, because the water temperature or the ambient temperature changes, the expansion and contraction of the length change of large value. For branch pipe or pipe joint pipe, the higher chance of leakage. Water separator is a kind of multiple branch joint water distribution, it uses multiple unidirectional cloth tube, each a water distribution pipe through the water and sanitary ware and the tap connection, to reduce or cancel the concealed pipes used in branch pipe or pipe joint.(4) pipeline crossing roof slab should be set casing, through the roof should be used when the metal casing, height must meet the standard requirements. The casing and the cracks without perfusion of fine stone concrete, shall not use the asphalt in Yau Ma Tei wire packing seal. Otherwise, if the floor area of water sewage easily along the pipe wall infiltration into the submucosa.(5) the role of automatic exhaust valve. In no time delay self-closing valve of the squat toilet building water supply system, such as schools, hotels, office buildings and other force in water supply pipe system, if the top with self-closing valve can well control the flow of water, but not very good control of airflow. When the system is cut off, water pipes often accumulate a large amount of air. System after water supply pipe, air may be compressed to the tube at the top of water to form a compressed air zone. When someone is pressed delay self-closing valve button, then the compressed air with water gushing out of the closet, often within the dirt blowing to above ground, even spilled onto the clothes closet.2 Drainage system(1)The UPVC pipe wall is white, very susceptible to pollution, so the use of the process should pay attention to protection, in the pipeline in place should be promptly after the plastic packaging bag, to be removed after the completion of the project.(2) Drainage pipe out door horizontal pipe and vertical pipe connection should be used when the two45. Elbow instead of90. Elbow, which is beneficial to the drainage. There are also some engineering design for the three plus examination export method. In some projects, product quality, leading to the three links are often damaged, inconvenient repair. So in thevertical pipe and main pipe is connected with the fixed support, parts. Vertical pipe through floor roof should be fixed as supporting points, and with sheath.(3) In the legislative branch, floor, to do the protection work. For UPVC tube light weight, should be timely plugging holes in floors, planted bracket. There are a number of projects, because there was no time to fill the hole plugging holes, civil engineering, causing destruction and pipeline slope and verticality of affected. The correct approach is to stand pipe after completion of construction, straightening and planted bracket, with a good fine stone concrete plugging hole. Branch floor, planted set hanger and plugging holes. Because the floor, floor drain and the straight tube exposed to the ground, easily damaged, precautions should be taken. The specific approach is: in the floor drain and the straight tube around the100arm UPVC tube saw small short circle in the floor drain and straight around, with a fine stone concrete protection, height of not more than civil screed. For ease of maintenance, pipe water trap should be above the floor slab, for apparatus with water storing bend. Because the UPVC pipeline is light weight, thin tube wall, should pay attention to using a muffler noise reduction function fitting.(4)Installed to meet the requirements. The interior floor is mounted high above the surface, will cause the water leakage is too low, on the ground to form a pit, affect the surface clean and inconvenience in walking.(5)Air nozzle shall be located in a building ( such as eaves cornice took part, balcony and canopy ) above, otherwise cause odor accumulation. In accordance with the relevant standard requirements, the people often activity of roof, roof vent pipe extends the height of not less than 2m, and try to set bracket.(6)High-rise building in the UPVC ~ B pipe, without taking the measures to prevent fire from spreading. According to the" hard vinyl chloride building drainage pipeline engineering" ( cJJ / T29 - 98) Regulations: high-rise buildings indoor drainage pipelines that apply settings and big diameter or equal to 11Omm, in vertical pipe through the floor should be set to fire the casing or fire blocking ring, to prevent the fire spreading to the upper layer through a pipeline.(7)The floor drain and trap with. No provisions for floor drain must set up a trap, but it can affect users. The general water supply and drainage standard atlas will take seal circular bell type floor drain to a, B, C, Ding Si, although the standard of water seal section height to makespecific provision, but there is a water storage, water due to water evaporation and destroyed. Manufacture and installation and often fails to meet the design requirements. All indoor undertake a fecal sewage drainage floor drain, shall be set the trap, this can effectively prevent odor phenomenon.(8) Sewage emergency discharge tube. For kitchen and toilet adjacent residential, kitchen, toilet is if separate drainage system, is straight at the bottom of two system for emergency discharge unicom. The correct approach is to lead a floor drain from the kitchen and toilet pipe or by a toilet to kitchen pipe system. Its purpose is to once - side discharge pipe suddenly jam, still discharge sewage overflows when the ground floor drain into another system from the outside, but not to the other indoor room large area sewage soaks inundates.3 Fire water supply system(1) The design of automatic sprinkler system for pipeline connection made the trench should be used to clamp connections, or wire joint, flange connection. The current widespread use of the automatic sprinkler system, generally with galvanized steel pipe galvanized pipe, and larger in diameter than the5Omm, pipe parts of poor quality, construction difficulty. Diameter of1OOmm welding work, will destroy the galvanized layer, causing the two galvanized, the effect is not ideal. As the hoop connection parts, to avoid the above problem, and the construction is simple, without welding, and the grooves can be precast. Now the groove type clamps connecting piece is stereotypes products, mature technology, spare parts complete, quality assurance. When the proposed pipeline diameter is larger than 50mm, the groove type clamps connecting piece.(2) As the applicator interface diameter is 15mm, so some construction spaces using15ram galvanized steel pipe small vertical tube connected with the nozzle, effects of fire extinguishing water ability, should adopt the25mm diameter pipe with different diameter pipe hoop. Some engineering support, support installation is not standardized, not according to the specified distance setting, defenseless and Akira bracket, directly affect water effect, should be strictly in accordance with the relevant standard, set Branch hanger.(3) Network to carry out maintenance and leakage test of strength test is performed in two steps. Some construction unit only to the network leakage test or test the pressure does not meet the requirements of design and codes, this will give the normal operation of the system brings hidden trouble.(4) Banned the use of plastic water supply pipe for fire water supply pipe, or in a building plastic water supply pipeline and fire water supply pipeline. Because plastic pipe heating after reduced intensity, fire will cause the pipeline damage, will not play the role of fire water supply. Plastic water supply pipe and fire pipes, fire, damage to the plastic pipe, easy leakage, there is no guarantee that a fire water and hydraulic pressure.(5) Must be in conformity with the requirements of fire hydrant installation. Some concealed in brick wall of fire hydrant boxes above the hole without lintel, by loading body is deformed, causing the box door is open. In addition the construction of some units to randomly change the fire hydrant at the end position of a preformed hole, and welding and cutting hole, leading to the installation, hydrant mouth can not be with the wall into 45or 90degree angle; or with the surrounding distance is too small, causing the fire hose cannot be installed to a fire hydrant or the tape to form bending effect of water.4 Water supply and drainage noise solutionIn addition to the requirements of water supply and drainage pipe and equipment layout should be consistent and building structure, water supply and drainage noise reduction. During construction, attention to details, can effectively reduce the noise generation.(1) In order to reduce the water hammer occurrence possibility, the outlet valve Shuizui and not using the rapid opening and closing of the water supply fittings.(2) In order to reduce the flow induced vibration noise, according to the condition of the water supply pipe and selection of density of sanitary ware, and according to the standard setting of pipe support and hanger. Different pipes with different support spacing requirements; design pipeline fixing bracket, also should consider from pipeline temperature changes caused by the expansion and contraction force.(3) To reduce the cavitation noise of ascending and descending pipe, for heating system of water distribution pipe top and to elevation of the pipe section should be equipped with automatic exhaust valve; downfeed system can use the highest water distribution point when a branch is deflated splitting meter, in the water vertical tube top with automatic exhaust valve.(4) Drainage system reduces the vertical pipe and horizontal branch connection angle, or a branch connecting the upper part special parts, reduce the horizontal branch pipe to water flow, to avoid the water jump phenomenon, thereby reducing the drainage noise.(5) Drainage pipe and drainage standpipe connection should be45 degrees,60 degreeselbow, three links, or set up a special accessories. Connections of the elbow should be composed of 2to 45 degrees elbow, and shall be on the elbows set supporting pier or bracket. In this way, can slow down the drain pipe and the drain pipe of the water flow in the water flow and vertical draining pipe wall impact noise.(6) To increase the horizontal trunk pipe and vertical pipe and horizontal trunk pipe connecting bend radius of curvature, or installed with reduced height of hydraulic jump, stable drainage pipe pressure function lower special accessories, to improve the horizontal trunk pipe drainage condition.5 Conclusion:Living, live as the mankind indispensable material conditions, is restricted by social productivity, at the same time, is also the social productivity development level indicates one of. From the initial human ancestor looking for natural caves and trees do sacrifice body are today a multi-storey and high-rise residential buildings and supporting a full range of public facilities of residential area, residential construction technology, marked the social productive forces to a new level. Today, our life has stridden to well-off, residential construction quality, indoor and outdoor environment improvement, so that our country's housing situation in recent years have varying degrees of change. In residential construction, although our country starts later, but the government has pledged, formulate corresponding policies, government departments to organize and mobilize all aspects involved in residential development plan, planning, design, construction and management. No doubt, this is a huge task, need government, the construction industry and the vast majority of the practitioners, down-to-earth to make unremitting efforts. Upgrade and improvement of our people 's living environment and living conditions. With the water supply and drainage pipe of continuous improvement, we should constantly sum up the design and installation of the experience lesson in the process, improve the general level of the installation. Professional supervision engineer shall be in this play a greater role in the. In the new century, building water supply and drainage will shoulder the historical responsibility, facing new challenges. Building water supply and drainage will be more prominent in the people-oriented principle, and will focus on the adjustment to the civil and industrial construction to pay equal attention to both, public buildings and residential buildings, water supply and water supply and water, water pressure, and water quality to pay equal attention to, direction, into a comprehensive, balanced,practical, safe development road.References[1] Li Wenqing, Shao Zhuang. Building fire water supply and some problems in construction. Heilongjiang water conservancy science and technology,2006(4).[2] Chen Zhentie. Building water supply and drainage specialty on the coordination [J ]. Water supply and drainage, l996(11).[3] king growth. Building water supply and sewerage engineering ( Fifth Edition ) [ M]. Beijing: China Building Industry Press,2005[4] GBJ242 82heating and sanitary engineering code for construction and acceptance of.[5] CJJ / T29 - 98building drainage pipeline project technical specification of hard vinyl chloride.[6] GB5026l96automatic sprinkler systems code for construction and acceptance of.浅谈建筑给排水施工中的常见问题及解决孙峰摘要：建筑给排水施工质量的好坏直接影响建筑物的使用。

多层住宅建筑给排水设计的几个问题摘要：本文就多层住宅建筑给排水设计中给水管材的选用，管道的敷设方式，水表出户设置，家用热水器的设置及空调冷凝水排放等问题进行探讨，并提出一些具体看法。

Abstract: this paper discussed some questions about selection of service pip laying methods,pipeline,water meter out of account settings,setting domestichot-water heater,and air-conditioning condensate emissions of ultilayer-WPM, and gave some specific advices.关键词：多层住宅给水管材管道敷设水表太阳能热水器Keyword: multilayer buildings, PPR, piping, water meter, solar water heater正文：多层住宅以其配套设施简单，造价低，物业管理方便等特点，很受中小城市房地产开发商和广大居民的欢迎。

如何按2000年小康住宅科技产业工程居住区规划设计导则的要求，提高住宅的设计水平，为每个住户营造出一个舒适的生活空间，是每个设计人员的职责所在。

作为住宅的心脏――厨房、卫生间，是功能复杂，卫生、安全和舒适度要求高，营造繁杂,技术要求高的空间。

因此，设计人员必须以整体设计的观念和方法，综合考虑厨房、卫生间给排水管道和设备的安装等。

下面就多层住宅给排水设计中给水管材的选用、管道的敷设、水表出户设置、家用热水器的设置和空调冷凝水排放等问题与同行们一起探讨。

（一）给水管材选用问题随着人们的生活质量不断提高,对自来水的水质要求也日趋提高。

据大量水质监测数据表明,导致管网水质恶化的主要原因是建筑物内供水管道采用传统的镀锌钢管的锈蚀所致。

试论建筑给排水设计中若干问题摘要：随着我国住宅建筑的崛起,建筑给排水专业也迅速发展,建筑给排水系统已成为现代建筑物的重要组成部分。

人们对居住环境的要求越来越高,对居住建筑内一些设施的布置、材料的选用、噪声的污染、节能环保等的要求也越来越高。

笔者结合在设计过程中的一些经验与体会，针对设计几个常见问题谈谈给排水设计中的一些特点,对存在的问题提出了一些解决办法,以供同行们参考。

关键词：建筑设计给排水问题分析措施Abstract: along with the rise of residential buildings in our country, construction drainage major also rapid development, construction drainage system has become an important part of the modern buildings. People living environment to demand more and more, to live within the building of some facilities layout, the material selection, noise pollution, energy conservation and environmental protection requirements of such as more and more is also high. The author in the design process of some of the experience and the experience, in view of the design of common problems talk about some of the drainage design characteristics, the existing problems and put forward some solutions, with reference to colleagues.Keywords: building water supply and drainage design problem analysis measures一、给水系统的压力问题高层建筑的给水系统按竖向分区分为高区供水和低区供水,低区供水一般采用带气压罐的变频供水系统,有的也采用高位水箱供水。

中英文对照外文翻译文献(文档含英文原文和中文翻译)原文：Optimum combination of water drainage,water supply and eco-environment protection in coal-accumulated basin of North ChinaAbstract The conflict among water drainage,water supply and eco-environment protection is getting more and more serious due to the irrational drainage and exploitation of ground water resources in coal-accumulated basins of North China.Efficient solutions to the conflict are tomaintain long-term dynamic balance between input and output of theground water basins,and to try to improve resourcification of the mine water.All solutions must guarantee the eco-environment quality.This paper presents a new idea of optimum combination of water drainage，water supply and eco-environment protection so as to solve theproblem of unstable mine water supply,which is caused by the changeable water drainage for the whole combination system.Both the management of hydraulic techniques and constraints in economy,society,ecology,environment,insustuial structural adjustments and sustainable developments have been taken into account.Since the traditional and separate management of different departments of water drainage,water supply and eco-environment protection is broken up these departments work together to avoid repeated geological survey and specific evaluation calculations so that large amount of national investment can be saved and precise calculation for the whole system can be obtained.In the light of the conflict of water drainage,water supply and eco-environment protection in a typical sector in Jiaozuo coal mine,a case study puts forward an optimum combination scheme,in which a maximum economic benefit objective is constrained by multiple factors.The scheme provides a very important scientific base for finding a sustainable development strategy.Keywords combination system of water drainage,water supply and eco-environment protection,optimal combination,resourcification of mine water.1Analyses of necessity for the combinationThere are three related problems in the basin.It is well known that the major mine-hydrogeological characteristics of the coal accumulated basin in North China display a stereo water-filling structure,which is formed by multi-layer aquifers connected hydraulically together with various kinds of inner or outer boundaries.Mine water hazards have seriously restricted the healthy development of coal industry in China because of more water-filling sources and stronger water-filling capacity in coal mines of the basin.Coal reserves in the basin are threatened by the water hazards.In Fengfeng,Xingtai,Jiaozuo,Zibao,Huaibei and Huainan coal mine districts,for example,it is estimatedthat coal reserves are threatened by the water hazards up to 52％,71.％40,％,60％,48％and 90％of total prospecting reserves respectively.It is obvious that un-mining phenomenon caused by the water hazards is serious.Water-bursting accidents under coal layers have seriously influenced safe production.Some statistical data show that there were 17 water-bursting accidents with over 1 m3/s inflow from 1985.Water drainage is an increasing burden on coal mines threatened by water hazards:high cost of water drainage raises coal prices and reduces profits of the enterprise.On the other hand,it is more and more difficult to meet the demand of water supply in coal mine districts in the basin.The reasons are not only arid and semi-arid weather conditions,but also a large amount of water drainage with deep drawdown in coal mines and irrational water exploitation.The deterioration of eco-environment is another problem.Phenomena of land surface karst collapse can be found.Many famous karst springs,which are discharge points for the whole karst groundwater syatem,stop flowing or their discharge rates decrease on a large scale.Desert cremophytes in large areas in west China die because of falling groundwater level.These three problems are related and contradictory.In order to solve the problems while ensuring safe mining,meeting water resource demands and slowing down the pace of eco-environment deterioration,it is necessary to study the optimum combination of water drainage,water supply and eco-environment protection in the basin.2The state of the art of research and the problemsAlthough research into the combination of water drainage and water supply started much earlier in some countries,their conception is simple and some shortcomings remain in their study on the theory and pattern of combination.China’s research history on the combination can be divided into three stages.The first stage is the utilization of mine water.A century ago mine water started to be used as water supply for mines.But the utilization scale and efficiency were quite limited at that time.The second stage is a comprehensive one:mine water was used while water hazards were harnessed.Great progress was made both in theory and practice of the combination.For example,the combination of water drainage and water supply not only means the utilization of mine water,but also means that it is a technique of preventing water hazards.It is unfortunate,however,that the combination research in this stage offered less sense ofeco-environment protection.Optimum combination management of water drainage,water supply and eco-environment protection is the third stage.Main features in this stage are to widen traditional research,and to establish an economic-hydraulic management model,in which safe mining,eco-environment protection and sustainable development demands,etc.are simultaneously considered as constraint conditions.3Trinity systemThe trinity system combines water drainage,water supply and eco-environment quality protection.The water-collecting structures of the system consist of land surface pumping wells in the mines,shallow land surface well in groundwater recharge areas and artificial relief wells under the mines.Both integration and coordination for the trinity system are distinguished according to the combination.The integration for the system means to utilize drainage water under the mines and pump water onto the land surface as water supply for different purposes without harming the eco-environmental quality.The coal mines are not only drainage sites,but also water supply sources.The purpose of drilling pumping wells on the land surface is to eliminate special influences on different consumers,which are caused by terminating drainage processes under the mines due to unexpected accidents in mining.The coordination for the system means to bulid some water supply sources for different consumers while ensuring eco-environmental quality in groundwater recharge positions,where pumping groundwater is quite effective on lowering groundwater heads in the mine areas.Itintercepts in advance the recharging groundwater flow towards the mines,which may not only provide consumers with good quality groundwater,achieve the goal of dropping down groundwater heads in the mines,but also effectively reduce the high costs of drainage and water treatment,which are needed by traditional dewatering measures with large drainage flow rates under the mines.The coordination changes the traditional passive pattern of preventing and controlling groundwater hazards under the mines into that of active surface interception.Both very developed karst flow belts and accumulated groundwater recharge ones under the ground are relatively ideal interceptive coordination positions in the system.For the integration of the trinity system,artificial relief wells under the mines and the land surface pumping wells mainly penetrate into direct thin bedded karst aquifers interbedded with the mining coal layers,while for the coordination of the system,the shallow land surface wells mainly penetrate into very thick karst aquifer.Therefore,hydrogeological conceptual model for the system involves the multi-layer aquifers connected hydraulically by different inner boundaries.Setting up stereo hydrogeological conceptual models and corresponding mathematical models is a prerequisite for solving the managemental problems for the system.Management of the trinity system not only considers the effects of lowering groundwater heads and safe operation for water drainage subsystem,but also pays attention to the water demands for water supply subsystem and quality changes for eco-environment protection subsystem.They play the same important role in the whole combination system.It controls the groundwater heads in each aquifer to satisfy the conditions of safe mining with certain water head pressures in the mines,and to guarantee a certain amount of water supply for the mines and near areas,but the maximum drawdown of groundwater must not be ex ceded,which may result in lowering eco-environmental quality.4Economic-hydraulic management modelIn the trinity system management,groundwater resources in the mines and nearby areas,which are assessed on the premise of eco-environment qualities and safe operation in the mines,may be provided as water supply prices,drainage costs,transportation costs(including pipeline and purchasing the land costs)and groundwater quality treatment costs for the three different waterconsumers,the optimum management models may automatically allocate to each consumer a certain amount of groundwater resources and a concrete water supply scenario based on comparisons of each consumer’s economic contribution to the whole system in objective function.Therefore the management studies on the optimal combination among water drainage,water supply and eco-environment protection involve both the management of groundwater hydraulic techniques and the economic evaluations,eco-environment quality protection and industrial structure programs.In addition to realizing an economic operation,they also guarantee a safe operation which is a key point for the combination of the whole system.5The management model for the trinity system can reach water supply goals with drainage water under the mines and the land surface pumping water on the premise of ensuring eco-environmental quality.And it can make use of one model to lay down comprehensively optimum management scenarios for each subsystem by means of selecting proper constraints and maximum economic benefit objective produced by multiple water consumers.The model can raise the security and reliability of operation for the whole trinity system,and the drainage water can be forecast for the mines and the management of water supply resource and the evaluation of eco-environment quality can be performed at the same time so as to respectively stop the separate or closed management,of departments of drainage water,water supply and eco-environment protection from geological survey stage to management evaluation.This,in economic aspect,can not only avoid much geological survery and special assessment work which are often repeated by the three departments,and save a lot of funds,but also ,in technical aspect,make use of one model to simultaneously consider interference and influence on each other for different groundwater seepage fields so as to guarantee calculating precision of the forecast,the management and the evaluation work.The economic-hydraulic management model can be expressed as follows.6 A case studyA typical sector is chosen.It is located in the east of Jiaozuo coal mine,Henan Province,China.Itconsists of three mines:Hanwang Mine,Yanmazhuang Mine and Jiulishan Mine.The land surface is flat,and the whole area is about 30 km2.An intermittent river Shanmen flows through the sector from the north to the south.Average annual precipitation in the sector is about 662.3mm.Theprecipitation mainly concentrates inJune,July,August and September each year.Strata in the sector consist of very thick limestone in Middle Ordovician,coal-bearing rock series in Permo Carboniferous and loose deposits in Quaternary.There are four groups of faulted structures.The first is in northeast-southwest direction such as F3 and F1..The second is in the northwest-southeast direction such as Fangzhuang fault.The third is in the east-west direction such as Fenghuangling fault.The last is almost in north-south.These faults are all found to be normal faults with a high degree of dip angle.Four major aquifers have been found in the sector.The top one is a semi-confined porous aquifer.The next one is a very thin bedded limeston aquifer.The third is a thin bedded limestone aquifer.The last one at the bottom is a very thick limestone aquifer.Objective function of the management model is designed to be maximum economic benefit produced by domestic,industrial and agricultural water supply.Policy making variables of the model are considered as the domestic,industrial and agricultural groundwater supply rates in every management time step,and they are supplied by artificial relief flow wells under the mines,the land surface pumping wells in the mines and the shallow land surface wells in the groundwater recharge areas.All the 135 policy making variables are chosen in the model,27 for drainage wells under the mines in aquifer,27 for the land surface pumping wells in the mine districts in aquifer 27 in aquifer 27 in aquifer O2 27 for the shallow land surface wells in aquifer O2Based on the problems,the following constraint conditions should be considered:(1)Safe mining constraint with groundwater pressure in aquifer L8.There are altogether three coalmines in the typical sector,i.e.Hanwang Mine,Yanmazhuang Mine and Jiulishan Mine.Elevations of mining level for these mines are different because it is about 88-150 m in the second mining level for Hanwang Mine,and -200m in the second mining level for Yanmazhuang Mine,and-225 m in the first mining level for Jiulishan Mine.According to mining experiences,pressure-loaded heights for groundwater heads in safe mining state are considered as about 100-130m.Therefore,the groundwater level drawdowns in the three management time steps for aquifer L8 at three mines have to be equivalent to safe drawdown values at least in order to pervert groundwater hazards under the mines and to guarantee their safe operation.(2)Geological eco-environment quality constraint.In order to prevernt groundwater leakage fromupper contaminater porous aquifer into bottom one and then to seepage further down to contaminate the thin bedded limestone aquifer in the position of buried outcrop,the groundwater heads in the bottom porous aquifer must keep a certain height,i.e.the groundwater drawdowns in it are not allowed to exceed maximum values.(3)Groundwater head constraint at the shallow land surface wells in aquifer O2,The shallow landsurface wells should penetrate in aquifer O2 in order to avoid geological environment hazards,such as karst collapse and deep karst groundwater contamination.Groundwater head drawdowns in aquifer O2 for the shallow land surface wells are not allowed to exceed criticalvalues.(4)Industrial water supply constraint for the groundwater source in aquifer O2 .The rate ofindustrial water supply needed by the planned thermal power plant in the north of the sectoris designed to be 1.5 m3/s according to the comprehensive design of the system in thesector.In order to meet the demands of water,the rate industrial water supply for thegroundwater source in aquifer O2 in every management time step must be equivalent at leastto 1.5 m3/s.(5)Maximum amount constraint of groundwater resource available for abstraction.In order tomaintain the balance of the groundwater system in the sector for a long time and to avoid anyharmful results caused by continuous falling of groundwater head,the sum of groundwaterabstraction in each management time step is not allowed to exceed the maximum amount ofgroundwater resource available for abstraction.Since there is not only water drainage in the mines,but also water supply in the whole combination system,management period for the model is selected from June 1,1978 to May 31,1979,in which annual average rate of precipitation is about 50％.Management time steps for the period are divided into three.The first one is from June to September,the second from October to next January,and the last one from next February to May.According to comprehensive information about actual economic ability,economic development program and industrial structure adjustment in the sector at present and in the near future,and different association forms of water collecting structures among the land surface pumping wells,the shallow land surface wells and artificial relief flow wells under the mines,this paper designs 12 management scenarious,all of which take the safe operation in the trinity system as the most important condition.After making comparisons of optimum calculation results for the 12 scenarious,this paper comes to a conclusion that scenarios is the most ideal and applicable one for the typical sector.This scenario not only considers the effective dewatering advantage of the artificial relief flow wells under the mines and safe stable water supply advantage of the land surface pumping wells,but also pays attention to the disadvantage of low safe guaranty rate for the relief flow wells under the mines for water supply and of large drilling investment in the land surface pumping wells.Meanwhile,eh shallow land surface wells inaquifer O2in this scenario would not only provide water supply for the thermal power plant as planned,but also play an important role in dewatering the bottom aquifer,which is major recharge source of groundwater for the mines.If the drainage subsystem under the mines runs normally,this scenario could fully offer the effective dewatering functions of the artificial relief flow wells under the mines,and makes the trinity system operate normally.But if the drainage subsystem has to stop suddenly because of unexpected accidents,the scenario could still fully utilize the land surface pumping wells and the shallow land surface wells,and increae their pumping rates in order to make up for temporary shortage of water supply for the trinity system and to make its economic losses reduced to a minimum extent.Increasing groundwater abstraction rate for the land surface pumping wells and the shallow land surface wells,in fact,is very favorable for harnessing the water-accidents under the mines and for recovery production of the mines.To sum up,this scenario sets up a new pattern for the combination of water drainage,water supply and eco-environment protection.It solves quite well the conflicts between the low safe guaranty rate and the effective dewatering result for the artificial relief flow wells under the mines.It makes full use of beneficial aspect of the conflicts,and meanwhile compensates for the unbeneficial one by arranging the land surface pumping wells in the coal mine districts.Therefore,this scenario should be comprehensive and feasible.In this scenario,Hanwan Mine,Yanmazhuang Mine and Jiulishan Mine are distributed optimally for certain amount of domestic and industrial water supply,but not for much agricultural water supply.The land surface pumping wells are also distributed for different purposes of water supply.The water supply for the thermal power plant (1.5 m3/s) is provided by the shallow land surface prehensive effects,produced by the above three kinds of water collecting structures,completely satisfy all of the constraint conditions in the management model,and achieve an extremely good economic objective of 16.520551million RMB yuan per year.In order to examine the uncertainty of the management model,12management scenarios are all tested with sensitive analysis.7Conclusion(1)The optimum combination research among water drainage,water supply and eco-environmentprotection is of great theoretical significance and application value in the basin of North China for solving unbalanced relation between water supply and demands,developing new potential water supply sources and protecting weak eco-environment.(2)The combination research is concerned not only with hydraulic technique management but alsowith constraints of economic benefits,society,ecology,environment quality,safe mining and sustainable development in the coal mines.(3)The combination model,for the first time,breaks up the closed situation existing for a longtime,under which the government departments of drainage water,water supply and eco-environment protection from geological survey stage to management evaluation work respectively.Economically,it can spare the repeated geological survey and special assessment work done by the three departments and save a lot of funds;technically,one model is made use of to cover the interference and influence each other for different groundwater seepage fields soas to guarantee a high calculating precision of the forecast,the management and the evaluation work.(4)The management scenario presented in the case study is the most ideal and applicable for thetypical sector.This scenario not only makes full use of the effective dewatering advantages of the artificial relief flow wells under the mines and safe stable water supply advantages of the land surface pumping wells,but also pays attention to the disadvantages of low safe guaranty rate for the relief flow wells under the mines for water supply and of large drilling investment for the land surface pumping wells.References1.Investigation team on mine-hydrogeology and engineering geology in the Ministry ofGeology and Mineral Resources.Investigation Report on Karst-water-filling Mines(inChinese).Beijing:Geological Publishing House,19962.Liu Qiren,Lin Pengqi,Y u Pei,Investigation comments on mine-hydrogeological conditionsfor national karst-water-filling mines,Journal of Hydrogeology and Engineering Geology(in Chinese),19793.Wang Mengyu,Technology development on preventing and curing mine water in coalmines in foreign countries,Science and Technology in Coal(in Chinese),19834.Coldewey,W.G.Semrau.L.Mine water in the Ruhr Area(Federal Republic of Germany),inProceedings of 5th International Mine Water Congress,Leicestershire:Quorn SelectiveRepro Limited,19945.Sivakumar,M.Morten,S,Singh,RN,Case history analysis of mine water pollution,inProceedings of 5th International Mine Water Congress,Leicestershire;Quorn SelectiveRepro Limited,19946.Ye Guijun.Zhang Dao,Features of Karst-water-filling mines and combination betweenwater drainage and water supply in China,Journal of Hydrogeology and EngineeringGeology(in China),19887.Tan Jiwen,Shao Aijun,Prospect analyses on Combination between water drainage andwater supply in karst water basin in northern China,Jounnal of Hebei College ofGeology(in Chinese),19858.Xin Kuide,Yu Pei,Combination between water drainage and water for seriouskarst-water-filling mines in northern China,Journal of Hydrogeology and Engineering Geology(in Chinese),19869.Wu Qiang,Luo Yuanhua,Sun Weijiang et al.Resourcification of mine water andenvironment protection,Geological Comments(in Chinese),199710.Gao Honglian,Lin Zhengping,Regional characteristics of mine-hydrogeological conditionsof coal deposits in China,Journal of Hydrogeology and Engineering Geology(in Chinese),198511.Jiang Ben,A tentative plan for preventing and curing measures on mine water in coal minesin northern China,Geology and Prospecting for Coaofield(in Chinese),1993中国北方煤炭积聚区的最佳组合排水，供水和生态环境保护摘要为了开采中国北方煤炭资源丰富的区域，不合理的排水使排水、供水和保护生态环境之间的冲突日趋严重。

关于住宅小区建筑给排水设计中的问题探讨摘要：给排水系统作为建筑工程的“血液”系统，对建筑的品质提升有着至关重要的作用，这就要求设计人员在设计过程中，在符合有关设计规范的基础上，充分考虑需求。

本文着重分析了给排水设计中存在的问题,并结合个人多年工作经验提出了在给排水设计中需要注意的问题和解决对策。

关键词：住宅小区；给排水设计；问题与对策Abstract: water supply and drainage system as building project “blood” system, improve the quality of the buildings have a vital role, this requires design personnel in the design process, in accord with the relevant design code, and on the basis of full consideration of the demand. This article mainly analyses the problems existing in the design of water supply and drainage, and connecting with the personal years of work experience in water supply and drainage design put forward the problems to be pay attention to and the countermeasures to solve problems.Keywords: residential district; Water supply and drainage design; Problems and countermeasures经济全球化的加剧，我国社会主义经济建设的发展速度日益提高，这使得人们的物质生活水平也得到显著性的提升，人们对与其日常生活相关的任何事物都有了更高的要求。

建筑工程及给排水专业中英文对照翻译Laminar and Turbulent FlowObservation shows that two entirely different types of fluid flow exist. This was demon- strated by Osborne Reynolds in 1883 through an experiment in which water was discharged from a tank through a glass tube. The rate of flow could be controlled by a valve at the outlet, and a fine filament of dye injected at the entrance to the tube. At low velocities, it was found that the dye filament remained intact throughout the length of the tube, showing that the particles of water moved in parallel lines. This type of flow is known as laminar, viscous or streamline, the particles of fluid moving in an orderly manner and retaining the same relative positions in successive cross- sections.As the velocity in the tube was increased by opening the outlet valve, a point was eventually reached at which the dye filament at first began to oscillate and then broke up so that the colour was diffused over the whole cross-section, showing that the particles of fluid no longer moved in an orderly manner but occupied different relative position in successive cross-sections. This type of flow is known as turbulent and is characterized by continuous small fluctuations in the magnitude and direction of the velocity of the fluid particles, which are accompanied by corresponding small fluctuations of pressure.When the motion of a fluid particle in a stream is disturbed, its inertiawill tend to carry it on in the new direction, but the viscous forces due to the surrounding fluid will tend to make it conform to the motion of the rest of the stream. In viscous flow, the viscous shear stresses are sufficient to eliminate the effects of anydeviation, but in turbulent flow they are inadequate. The criterion which determines whether flow will be viscous of turbulent is therefore the ratio of the inertial force to the viscous force acting on the particle. The ratioμρvl const force Viscous force Inertial ?= Thus, the criter ion which determines whether flow is viscous or turbulent is the quantity ρvl /μ, known as the Reynolds number. It is a ratio of forces and, therefore, a pure number and may also be written as ul /v where is the kinematic viscosity (v=μ/ρ).Experiments carried out with a number of different fluids in straight pipes of different diameters have established that if the Reynolds number is calculated by making 1 equal to the pipe diameter and using the mean velocity v , then, below a critical value of ρvd /μ = 2000, flow will normally be laminar (viscous), any tendency to turbulence being damped out by viscous friction. This value of the Reynolds number applies only to flow in pipes, but critical values of the Reynolds number can be established for other types of flow, choosing a suitable characteristic length such as the chord of an aerofoil in place of the pipe diameter. For a given fluid flowing in a pipe of a given diameter, there will be a critical velocity of flow corresponding to the critical value of the Reynolds number, below which flow will be viscous.In pipes, at values of the Reynolds number > 2000, flow will not necessarily be turbulent. Laminar flow has been maintained up to Re = 50,000, but conditions are unstable and any disturbance will cause reversion to normal turbulent flow. In straight pipes of constant diameter, flow can be assumed to be turbulent if the Reynolds number exceeds 4000.Pipe NetworksAn extension of compound pipes in parallel is a case frequently encountered in municipal distribution system, in which the pipes are interconnected so that the flow to a given outlet may come by several different paths. Indeed, it is frequently impossible to tell by inspection which way the flow travels. Nevertheless, the flow in any networks, however complicated, must satisfy the basic relations of continuity and energy as follows:1. The flow into any junction must equal the flow out of it.2. The flow in each pipe must satisfy the pipe-friction laws for flow in a single pipe.3. The algebraic sum of the head losses around any closed circuit must be zero.Pipe networks are generally too complicated to solve analytically, as was possible in the simpler cases of parallel pipes.A practical procedure is the method of successive approximations, introduced by Cross. It consists of the following elements, in order:1. By careful inspection assume the most reasonable distribution of flows that satisfies condition 1.2. Write condition 2 for each pipe in the formh L = KQ n(7.5) where K is a constant for each pipe. For example, the standard pipe-friction equation would yield K= 1/C2and n= 2 for constant f. Minor losses within any circuit may be included, but minor losses at the junction points are neglected.3. To investigate condition 3, compute the algebraic sum of the head losses around each elementary circuit. ∑h L= ∑KQ n. Consider losses from clockwise flows as positive, counterclockwise negative. Only by good luck will these add tozero on the first trial.4. Adjust the flow in each circuit by a correction, ΔQ , to balance the head in that circuit and give ∑KQ n = 0. The heart of this method lies in the determination of ΔQ . For any pipe we may writeQ = Q 0 ＋ΔQwhere Q is the correct discharge and Q 0 is the assumed discharge. Then, for a circuit100/Q h n h Q Kn Q K Q L L n n ∑∑∑∑?-=-=- (7.6) It must be emphasized again that the numerator of Eq. (7.6) is to be summed algebraically, with due account of sign, while the denominator is summed arithmetically. The negative sign in Eq.(7.6) indicates that when there is an excess of head loss around a loop in the clockwise direction, the ΔQ must be subtracted from clockwise Q 0’s and added to counterclockwise ones. The reverse is true if there is a deficiency of head loss around a loop in the clockwise direction.5. After each circuit is given a first correction, the losses will still not balance because of the interaction of one circuit upon another (pipes which are common to two circuits receive two independent corrections, one for each circuit). The procedure is repeated, arriving at a second correction, and so on, until the corrections become negligible.Either form of Eq. (7.6) may be used to find ΔQ . As values of K appear in both numerator and denominator of the first form, values proportional to the actual K may be used to find the distribution. Thesecond form will be found most convenient for use with pipe-friction diagrams for water pipes.An attractive feature of the approximation method is thaterrors in computation have the same effect as errors in judgment and will eventually be corrected by the process.The pipe-networks problem lends itself well to solution by use of a digital computer. Programming takes time and care, but once set up, there is great flexibility and many man-hours of labor can be saved.The Future of Plastic Pipe at Higher PressuresParticipants in an AGA meeting panel on plastic pipe discussed the possibility of using polyethylene gas pipe at higher pressures. Topics included the design equation, including work being done by ISO on an updated version, and the evaluation of rapid crack propagation in a PE pipe resin. This is of critical importance because as pipe is used at higher pressure and in larger diameters, the possibility of RCP increases.Se veral years ago, AGA’s Plastic Pipe Design Equation Task Group reviewed the design equation to determine if higher operating pressurescould be used in plastic piping systems. Members felt the performance of our pipe resins was not truly reflected by the design equation. It was generally accepted that the long-term properties of modern resins far surpassed those of older resins. Major considerations were new equations being developed and selection of an appropriate design factor.Improved pipe performanceMany utilities monitored the performance of plastic pipe resins. Here are some of the long-term tests used and the kinds of performance change they have shown for typical gas pipe resins.Elevated temperature burst testThey used tests like the Elevated Temperature Burst T est, inwhich the long-term performance of the pipe is checked by measuring the time required for formation of brittle cracks in the pipe wall under high temperatures and pressures (often 80 degrees C and around 4 to 5-MPa hoop stress). At Consumers Gas we expected early resins to last at least 170 hrs. at 80 degrees C and a hoop stress of 3 MPa. Extrapolation showed that resins passing these limits should have a life expectancy of more than 50 yrs. Quality control testing on shipments of pipe made fromthese resins sometimes resulted in product rejection for failure to meet this criterion.At the same temperature, today’s resins last thousands of hours at hoop stresses of 4.6 MPa. Tests performed on pipe made from new resins have been terminated with no failure at times exceeding 5,700 hrs. These results were performed on samples that were squeezed off before testing. Such stresses were never applied in early testing. When extrapolated to operating conditions, this difference in test performance is equivalent to an increase in lifetime of hundreds (and in some cases even thousands) of years.Environmental stress crack resistance testSome companies also used the Environmental Stress Crack Resistance test which measured brittle crack formation in pipes but which used stress cracking agents to shorten test times.This test has also shown dramatic improvement in resistance brittle failure. For example, at my company a test time of more than 20 hrs. at 50 degrees C was required on our early resins. Today’s resins last well above 1,000 hrs. with no failure.Notch testsNotch tests, which are quickly run, measure brittle crack formation in notched pipe or molded coupon samples. This isimportant for the newer resins since some other tests to failure can take very long times. Notch test results show that while early resins lasted for test times ranging between 1,000 to 10,000 min., current resins usually last for longer than 200,000 min.All of our tests demonstrated the same thing. Newer resins are much more resistant to the growth of brittle crack than their predecessors. Since brittle failure is considered to be the ultimate failure mechanism in polyethylene pipes, we know that new materials will last much longer than the old. This is especially reassuring to the gas industry since many of these older resins have performed very well in the field for the past 25 yrs. with minimal detectable change in properties.While the tests showed greatly improved performance, the equation used to establish the pressure rating of the pipe is still identical to the original except for a change in 1978 to a single design factor for all class locations.To many it seemed that the methods used to pressure rate our pipe were now unduly conservative and that a new design equation was needed. At this time we became aware of a new equation being balloted atISO. The methodology being used seemed to be a more technically correct method of analyzing the data and offered a number of advantages.Thermal Expansion of Piping and Its CompensationA very relevant consideration requiring careful attention is the fact that with temperature of a length of pipe raised or lowered, there is a corresponding increase or decrease in its length and cross-sectional area because of the inherent coefficient of thermal expansion for the particular pipe material. The coefficient of expansion for carbon steel is 0.012 mm/m?Cand for copper 0.0168mm/m?C. Respective module of elasticity a re for steel E = 207×1.06kN/m2 and for copper E = 103×106 kN/m2. As an example, assuming a base temperature for water conducting piping at 0?C, a steel pipe of any diameter if heated to 120?C would experience a linear extension of 1.4 mm and a similarly if heated to copper pipe would extend by 2.016 mm for each meter of their respective lengths. The unit axial force in the steel pipe however would be 39% greater than for copper. The change in pipe diameter is of no practical consequence to linear extension but the axial forces created by expansion or contractionare con- siderable and capable of fracturing any fitments which may tend to impose a restraint;the magnitude of such forces is related to pipe size. As an example,in straight pipes of same length but different diameters, rigidly held at both ends and with temperature raised by say 100?C, total magnitude of linear forces against fixed points would be near enough proportionate to the respective diameters.It is therefore essential that design of any piping layout makes adequate com- pensatory provision for such thermal influence by relieving the system of linear stresses which would be directly related to length of pipework between fixed points and the range of operational temperatures.Compensation for forces due to thermal expansion. The ideal pipework as far as expansion is concerned, is one where maximum free movement with the minimum of restraint is possible. Hence the simplest and most economical way to ensure com- pensation and relief of forces is to take advantage of changes in direction, or where this is not part of the layout and long straight runs are involved it may be feasible to introducedeliberate dog-leg offset changes in direction at suitable intervals.As an alternative,at calculated intervals in a straight pipe run specially designed expansion loops or “U” bends should be inserted. Depending upon design and space availability, expansion bends within a straight pipe run can feature the so called double offset “U” band or thehorseshoe typ e or “lyre” loop.The last named are seldom used for large heating networks; they can be supplied in manufacturers’ standard units but require elaborate constructional works for underground installation.Anchored thermal movement in underground piping would normally be absorbed by three basic types of expansion bends and these include the “U”bend, the “L”bend and the “Z”bend.In cases of 90 changes indirection the “L” and “Z”bends are used.Principles involved in the design of provision for expansion between anchor points are virtually the same for all three types of compensator. The offset “U” bend is usually made up from four 90° elbows and straight pipes; it permits good thermal displacement and imposes smaller anchor loads than the other type of loop. This shape of expansion bend is the standardised pattern for prefabricated pipe-in-pipe systems.All thermal compensators are installed to accommodate an equal amount of expansion or contraction; therefore to obtain full advantage of the length of thermal movement it is necessary to extend the unit during installation thus opening up the loop by an extent roughly equal the half the overall calculated thermal movement.This is done by “cold-pull” or other mechanical means. The total amount of extension between two fixed pointshas to be calculated on basis of ambient temperature prevailing and operational design temperatures so that distribution of stresses and reactions at lower and higher temperatures are controlledwithin permissible limits. Pre-stressing does not affect the fatigue life of piping therefore it does not feature in calculation of pipework stresses .There are numerous specialist publication dealing with design and stressing calculations for piping and especially for proprietary piping and expansion units; comprehensive experience back design data as well as charts and graphs may be obtained in manufacturers’publications, offering solutions for every kind of pipe stressing problem.As an alternative to above mentioned methods of compensation for thermal expansion and useable in places where space is restricted, is the more expensive bellows or telescopic type mechanical compensator. There are many proprietary types and models on the market and the following types of compensators are generally used.The bellows type expansion unit in form of an axial compensator provides for expansion movement in a pipe along its axis; motion in this bellows is due to tension or compression only.There are also articulated bellows units restrained which combine angular and lateral movement; they consist of double compensator units restrained by straps pinned over the center of each bellowsor double tied thus being restrained over its length.Such compensators are suitable for accommodating very pipeline expansion and also for combinations of angular and lateral movements.层流与紊流有两种完全不同的流体流动形式存在，这一点在1883年就由Osborne Reynolds 用试验演示证明。

给排水工程外文翻译 Final approval draft on November 22, 2020Short and Long Term Advantage roof drainage design performanceDecade has witnessed great changes in the design of the roof drainage system recently, particularly, siphon rainwater drainage system has been gradually improved, and there is likely to be the key application. At the same time these changes, urban drainage system design has undergone tremendous changes, because the scope of a wider urban drainage system design for sustainable development, as well as people for climate change flooding more attention. The main contents of this article is how to design roof drainage systems and make a good performance. Special attention is how to get rid of bad habits already formed the design, but also need to consider innovative roof drainage system, such as green roofs and rainwater harvesting systems.Practical application: In the past few years, the design of the roof rainwater drainage system has undergone tremendous changes. On large buildings, siphon rainwater drainage technology has been very common, as well as green roofs because it is conducive to green development, being more and more applications. Taking into account the ongoing research, this article focuses on how to effectively design a variety of roof rainwater drainage system, and make it achieve the desired design effect.1. IntroductionIn the past decade, the city and the water drainage system design has been widely accepted thinking about sustainable urban drainage system, or the optimal management direction. The main principles of the design of these systems is both a local level in line with the quality of development, but also to create some economic benefits for the investors. This principle has led to the development of new changes in the sump. Although the application of such a device is gradually reduced, but the urban environment relatively high demand areas still require 100% waterproof and rapid drainage, such as the roof. Typically roof drainage system in the design, construction and maintenance has not been given due attention. Although the drainage system investment costs account for only a small portion of the total construction investment, but not able to judge the loss caused by poor design.There are two different forms of roof drainage system design methods, namely the traditional and siphon method. Traditional systems rely on atmospheric pressure work, the drive ram affectedsink flow depth. Therefore, the conventional roof drainage systems require a relatively large diameter vertical drop tube, prior to discharge, all devices must be connected to the groundwatercollection pipe network. In contrast, siphonic roof drainage pipe systems are generally designed to full flow (turbulent flow meansthat require less exhaust pipe), which will form a negative pressure, the larger the higher flow rate and pressure head. Typically siphon system requires less down pipe work under negative pressure to the water distribution network can mean higher altitude work, thereby reducing the amount of underground pipe network.Both systems consists of three parts: the roof, rainwater collection pipes, pipe network.All of these elements are able to change the water pressure distribution system. This section focuses on the role and performance of each part. Due to the principle of siphon system has not been well understood, resulting argument is relatively small, this article will highlight siphon system.2. RoofThe roof is usually designed by the architect, designer and not by the drainage design. There are three main roof.2.1 Flat roofFlat roofs are used in industrial buildings less rainfall regions and countries. This roof is not completely flat, but lower than the minimum roof slope may require. For example, the United Kingdom require maximum slope of 10 °. Setting minimum slope in order to avoid any unnecessary water.Despite the flat roof if it is not properly maintained will have more problems, but it will reduce the dead zone within the building, and the ratio of sloping roofs in favor of indoor air.2.2 sloping roofsMost residential and commercial buildings are pitched roof, inclined roof is the biggest advantage can quickly drain, thereby reducing leakage. In temperate regions, we need to consider carrying roof snow load. Once it rains, rainfall through the sloping roofs can be determined by calculation. When rainfall data can be used, you can use the kinematic theory to solve such problems.2.3 green roof (flat or inclined)It can prove roof is the oldest green roofs, including rainfall can reduce or disperse roof planted with plants. It can be planted with trees and shrubs roof garden, it can also be a vegetated roof light carpet. Wherein the latter technique has been widely used. Some of these applications tend to focus on aesthetic requirements and are often used in green development. Since the aesthetic requirements and pressure requirements, as well as green roofs thermal insulation function, reduce the heat island effect, silencer effect, extend the life of the roof.Green roofs in Germany, the most widely used, followed in North America, but to consider the impact on the aesthetics. Germany is by far the most experienced countries in the 19th century have practical application, then as an alternative to reduce the risk of fire tarroof an option in urban areas. Germany is currently the main research question on the cultivation of other issues to consider smaller cities. A study from 1987 to 1989, was found packed with 70 mm thick green roof can be reduced by 60% -80% of heat loss. In a Canadianwork computer model based on the roof indicates that as long as the sump, the area can reach 70% of the roof area can be reduced by 60 percent in one year, the same model was also used for artificial rainfall, which the results indicate that rainfall in the catchment season helps to drain away rainwater.However, none of these studies show that green roofs can play a useful role in the rainfall season, or how high collection efficiency of water supply. The United States did some tests, as long as the green roofs regular watering, can reduce 65 percent of the runoff ina rainfall. America's most authoritative green roof guidelines by the New Jersey state environmental agencies promulgated. The mainprinciple is to solve the structural problems of light, and how can the normal drainage after two years.Rainfall period is based on the probability of failure is determined. The system is typically based on rainfall during rainstorms two minutes, two minutes, have a choice. Although this model will get more traffic, but there is no other better alternative. Studies have shown that the traditional model is applied to study green roofs are premature.Loss factor than traditional roof records should be small, about 98.7%.Peak flow will be reduced, although not penetrate, the surface roughness but also have a significant impact.Concentrated rainfall than two minutes for a long time,especially for large roof areas, such as public buildings, commercial buildings, industrial buildings.Urban drainage design should also consider other factors, for a complex system, a green roof in a rain is not enough. Water flow duration curve shows a longer than traditional systems. And two independent and will affect between is possible, which requires a more precise time period.3. Rainwater CollectorBasic requirements rainwater collector is designed to be able to accommodate rainfall rainstorms. Although it is possible to make a slightly inclined roof drainage purposes, but the nature of the construction industry and building settlement will become flat roofTypically, the tank is placed in a horizontal, sectional view of the water is outwardly inclined, which the role of hydrostatic.3.1 drain outletAnalyzing rainwater collector has sufficient volume is the key to the sump outlet external setting conditions. Also affect the flow rate into the storm water drainage system piping, but also affect the depth of the water catchment. Although the depth of the sump will not bring any particular problems, but too deep can cause excessive sump.Numerous studies in the 1980s showed that the flow of conventional roof drainage system outlet can be divided into two cases. It depends on the size of the depth and size of the outlet. When the water depth is less than half the diameter of the outlet, the flow of the first type, and the outlet of the flow can be calculated by an appropriate equation; water depth increases, exports are slowly clogging the flow will become another form forms, at the same time, the flow of exports can be obtained through other equations. While conventional roof drainage systems are designed to be free-draining, but may cause limitations encountered in the design of the flow is not free. In this case, it will require additional depth.Siphon roof drainage systems, the outlet is designed to be submerged stream. In this case, the depth of the outlet of the decision is more complicated, because the design of the sump depends on the flow. Recent studies have shown that conventional roof drainage systems use a variety of non-standard catchment, their depth and height, bigger than the diameter of the outlet. This will eventually result in a siphon effect. For a given catchment, the flow depends on the starting end of the drop tube diameter. A similar phenomenon has also been used to study the standard catchment, in these circumstances, only limited siphon action occurs within relatively close distance from the exit.3.2 tank flow classificationIn the complex flow sump outlet flow classification, can be seen from Table 2a, the flow will be uniform layering, regardless of whether the same inlet flow. Table 2b and 2c show, exportdistribution will greatly influence the flow.When the outlet is not a free jet, sump outlet complex flow classification is difficult to describe. Because each catchment tank pressures are likely to be merged. For example, the siphon tube system design point is at near full jet outlet flow classification depends on the energy loss of each branch.3.3 hydrostatic sectionalSump shape of the water surface in the canal can be classified according to the flow equation. In most cases, a low flow rate meansthat there is less friction loss, if exports are free jet, thefriction loss is negligible cross-section through the hydrostatic equation 1 to determine the horizontal distance.Where Q-- flow (m3 / s)T- surface width (m)g- acceleration of gravity (m / s2)F- flow area (m2)Equation 1 can not be ignored when the friction required to correct (or very long pipe velocity is large), or not a free jet.3.4 The current design methodsThe previous discussion has highlighted the main factors that should be considered with sink design. However, without the help of a certain number of models, computing hydrostatic sectional roof drainage system, the volume of the sump is possible. This large commercial and manufacturing industry, is a development opportunity, you can merge several kilometers of water routes. Thus, the conventional drainage system sump design methods are mainly based on experience, and assume that exports are free jet.Sump location in the building, it may cause the example to fail. Different interface sumpExcept in the case cited above, but also allows designers to use empirical data.3.5 Digital ModelLarge number of digital models can be used to accurately describe the flow of any form of catchment tank, regardless of whether the roof flows stable. An example of this model is a combination of roof space model. This model enables users to classify different aspects of the data indicated, includes: details of the rains, the roof surface drainage and other details. Kinematics have also been used to study rainwater tank to flow from the research collection. A typical method is based on open system to solve a basic problem of spatial mobility. This model automatically resolve the sump outlet flow situation, but also to deal with the case of free jet can also be simulated space limited mobility and submerged discharge. Output values include depth and flow rate.Currently, the model is essentially just a variety of research tools, but also through practical engineering test. However, we should face up to the various role models.4 pipe systems groupComposition in the form and scope of the tube group determinesthe roof drainage system relies mainly on the traditional system or siphon action.4.1 Traditional stormwater systemsConventional roof drainage systems, the ground plane is generally vertical pipe-line network, connected to the sump outlet and underground drainage systems, critical systems as well as compensating tube. It should be emphasized that the angle between the ground and the compensating tube is less than 10 °. Capacity of the entire system relies mainly on the outlet tube instead of down.Flow vertical tube is usually free-flowing, full of only 33%, the efficiency depends on the excess length of the tube. If the drop tube long enough (typically greater than 5m), there may be an annular flow. Similarly, under normal circumstances flow compensation pipe is free-flowing, full of up to 70%. Such designed process both for the design, various equations can also be used.4.2 Siphon roof drainage systemIn contrast with the traditional drainage systems, Siphon roof drainage system relies on air flow outside the system, and the tubeis full pipe flow stream.The designs are usually made on the assumption that the design of heavy rain, the system can quickly siphon discharge rainwater. This assumption allows the application of hydrostatic siphon system theory. Often used steady flow energy equation. While this approach ignores the small amount of energy loss at the entrance, but after the experiment showed that there are still conducive to practical use.However, steady-state design methods in the siphon system is exposed to rain when the system does not meet the standard requirements or changes in rainfall intensity is large is not applied. In the first case, there will be some mixing of air quality, annular flow occurs. These problems are not integrated in the system when more serious. Because usually designed rains are common, it is clear now design methodology over time may not apply to siphon system. This is a major disadvantage, because the design of the main problem isthe noise and vibration problems.Despite the disadvantages of the prior design approach, but a lot of the world's very few engineering failure reports. When a failure occurs, most likely for the following reasons:An incorrect understanding of the operation pointsSubstandard materials listInstallation defectsMaintenance mismanagementTo overcome these disadvantages, we have recently launched aseries of research projects, to discuss the siphon system, and the development of digital models. From this work we learn a lot.In contrast with conventional design methods of some assumptions, siphon system mainly has the following aspects:1) non-flow system of full flow2) levels of certain pipe-flowing full pipe flow3) full pipe flow downstream propagation through a vertical pipe, riser, etc.4) the inner tube flow occurs over the vertical section, the system to reduce the pressure5) downward tube is full pipe flow, there will be air lock6) appears completely siphon action until well into the air system is lower than a certain levelTable 4a column data indicate that below the design point, the system will siphon unstable flow, depth of the water collecting tank is insufficient to maintain the siphon action. Table 4b show that the unsteady flow in siphon system when it will appear.Table 5 lists the data output of a digital model. It can be seen that the model can accurately describe the siphon action, siphon and steady state, the data also show that the model can accurately describe the complex siphon action.5 ConclusionThis article has illustrated the critical roof drainage systems, but these are often overlooked in the urban drainage system design. This article also shows that the design process is a complex process, rely mainly on the performance of exports. The following conclusions are based on the design summed up:1) Run depend on three interacting parts: the roof, sump, water pipes2) Green roofs can reduce traffic and beautify the city3) the export performance of the system is essential4) siphon drainage system have a greater advantage in large-scale projects, but must be considered high maintenance costs5) Design siphon drainage system should consider additional capacity and operational issuesAlthough the green roof is a more attractive option, but the traditional roof of a building in the country will continue to dominate. Green roofs will be gradually developed, and gradually been widely accepted. Similarly, the roof drainage system shown effective that it will continue to play a huge role in the commercial building drainage systems.Roof drainage system of the greatest threats from climate change, existing systems tend to be not simply aging; rainfall patterns of change will result in inefficient operation, self-cleaning rate will be reduced. Changes in wind speed and the roof will also accelerate the aging of the roof, it is necessary to carry out maintenance. Taking into account the climate change, the increase in materials, roof collected rainwater will be more extensive. Currently, the amount of rain around the globe per person per day 7-300 liters in the UK, with an average consumption of 145L / h / d, of which onlyabout one liter is used by people, about 30 per cent of the toilet, study shows If water shortage, rainwater collected on the roof of developed and developing countries are recommended approach.屋顶排水设计性能的近期与远期优势最近十年见证了屋顶排水系统设计方面的巨大变化，特别的是，虹吸雨水排水系统已经得到逐步改善，并且有可能得到重点应用。

建筑给水排水基本术语中英对照翻译建筑给水排水基本术语中英对照翻译中德工程建筑设施智能技术093132 张伟）1、给水工程water supply engineering 原水取集和处理以及成品水输配工程。

2、排水工程sewerage ,wastewater engineering 收集、输送、处理和处置废水工程。

3、给水系统water supply system 给水取水、输水、水质处理和配水等设施以一定方式组合成总体。

4、排水系统sewerage system 排水收集、输送、水质处理和排放等设施以一定方式组合成总体。

5、给水水源water source 给水工程所取用原水水体。

6、原水raw water 由水源地取来原料水。

7、地表水surface water 存在于地壳表面，暴露于大气水。

8、地下水ground water 存在于地壳岩石裂缝或土壤空隙中水。

9、苦咸水（碱性水） brackish water ,alkaline water 碱度大于硬度水，并含大量中性盐，PH 值大于7。

10、淡水fresh water 含盐量小于500mg/L 水。

11、冷却水cooling water 用以降低被冷却对象温度水。

12、废水wastewater 居民活动过程中排出水及径流雨水总称。

它包括生活污水、工业废水和初雨径流以及流入排水管渠其它水。

13、污水sewage ,wastewater 受一定污染来自生活和生产排出水。

14、用水量water consumption 用水对象实际使用水量。

15、污水量wastewater flow ,sewage flow 排水对象排入污水系统水量。

16、用水定额water flow norm 对不同排水对象，在一定时期内制订相对合理单位排水量数值。

17、排水定额wastewater flow norm 对不同排水对象，在一定时期内制订相对合理单位排水量数值。