72-664: Nam Wan Tunnel is a tunnel in Hong Kong opened to traffic on 20 December 2009, along with the West Tsing Yi Viaduct , East Tsing Yi Viaduct and Stonecutters Bridge . The road tunnel, which forms an important part of the HK$ 15 billion Route 8 , linking Tsing Yi and Sha Tin in the city, began construction since 2003 and was completed in 2007. The twin-tube tunnel, built by the Highways Department of
144-444: A Community Chest Walk for Millions was held on 15 November 2009 to allow the public to walk across Stonecutters Bridge and East Tsing Yi Viaduct and through Nam Wan Tunnel. Over 30,000 participants took part, raising more than HK$ 10 million for the charity's Children and Youth Services. Tunnel A tunnel is an underground or undersea passageway. It is dug through surrounding soil, earth or rock, or laid under water, and
216-695: A canal . The central portions of a rapid transit network are usually in the tunnel. Some tunnels are used as sewers or aqueducts to supply water for consumption or for hydroelectric stations. Utility tunnels are used for routing steam, chilled water, electrical power or telecommunication cables, as well as connecting buildings for convenient passage of people and equipment. Secret tunnels are built for military purposes, or by civilians for smuggling of weapons , contraband , or people . Special tunnels, such as wildlife crossings , are built to allow wildlife to cross human-made barriers safely. Tunnels can be connected together in tunnel networks . A tunnel
288-499: A better cause. The Chest always encourages the younger generation to take an active role in serving the community and the annual "Flag Day" provides an ideal channel for the youth to realise their benevolent initiatives. Each year, more than 12,000 students and volunteers from primary and secondary schools, kindergartens, the Chest's member agencies, as well as other voluntary organisations participate in "Street Flag Sale". Together with
360-426: A joint award scheme. Under this programme, special events are organised to seek both corporate and public support. Love Teeth Day aims to arouse public awareness on oral health whilst raising funds for the needy. In return, a "Love Teeth Day Pack" with various oral care products will be presented to participants as gesture of appreciation. Green Day aims to arouse public awareness on environmental protection and, at
432-449: A large factor in the decision making process. Civil engineers usually use project management techniques for developing a major structure. Understanding the amount of time the project requires, and the amount of labor and materials needed is a crucial part of project planning. The project duration must be identified using a work breakdown structure and critical path method . Also, the land needed for excavation and construction staging, and
504-467: A pipe jack, with the span of some box jacks in excess of 20 metres (66 ft). A cutting head is normally used at the front of the box being jacked, and spoil removal is normally by excavator from within the box. Recent developments of the Jacked Arch and Jacked deck have enabled longer and larger structures to be installed to close accuracy. There are also several approaches to underwater tunnels,
576-509: A portal building at each end. They were formed by blasting through granite and volcanic rocks. The tunnel cross section is in the form of an arch . The approximate height and width of the arch is 11.2m and 15.3m respectively. The geology comprises coarse volcanic ash tuff on the west side and medium grained granite on the eastern side. Both of these lithologies are intruded by Rhyolite dykes together with some porphyrytic granite and occasional basalt dykes. The two tubes were constructed using
648-421: A specialized method called clay-kicking for digging tunnels in clay-based soils. The clay-kicker lies on a plank at a 45-degree angle away from the working face and rather than a mattock with his hands, inserts with his feet a tool with a cup-like rounded end, then turns the tool with his hands to extract a section of soil, which is then placed on the waste extract. Clay-kicking is a specialized method developed in
720-434: A tube can be sunk into a body of water, which is called an immersed tunnel. Cut-and-cover is a simple method of construction for shallow tunnels where a trench is excavated and roofed over with an overhead support system strong enough to carry the load of what is to be built above the tunnel. There are two basic forms of cut-and-cover tunnelling: Shallow tunnels are often of the cut-and-cover type (if under water, of
792-747: A tunnel than a sufficiently strong bridge). Some water crossings are a mixture of bridges and tunnels, such as the Denmark to Sweden link and the Chesapeake Bay Bridge-Tunnel in Virginia . There are particular hazards with tunnels, especially from vehicle fires when combustion gases can asphyxiate users, as happened at the Gotthard Road Tunnel in Switzerland in 2001. One of the worst railway disasters ever,
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#1732790461790864-432: A tunnel. Bridges usually require a larger footprint on each shore than tunnels. In areas with expensive real estate, such as Manhattan and urban Hong Kong , this is a strong factor in favor of a tunnel. Boston's Big Dig project replaced elevated roadways with a tunnel system to increase traffic capacity, hide traffic, reclaim land, redecorate, and reunite the city with the waterfront. The 1934 Queensway Tunnel under
936-661: A wide range of community projects. The goal of The Community Chest is to work for the betterment of Hong Kong through the support by millions and to build a caring society through greater participation and giving by the Hong Kong community. The mission statements of the Community Chest are: The Community Chest is governed by a Board. Under the Board, there are four main committees: the Executive Committee,
1008-461: Is a day when participants can dress in their favourite wear to work or to school and at the same time to raise funds for charity. It has run become a popular fund-raising event with an increasing number of participants every year. Each participant who raises/donates HK$ 60 can join the event while no minimum is set for student participants. As more and more employers began to encourage their employees to go to work in their casual wear, "Dress Casual Day"
1080-546: Is allowed in this tunnel tube, and motorcyclists are directed to the other tube. Each level was built with a three-lane roadway, but only two lanes per level are used – the third serves as a hard shoulder within the tunnel. The A86 Duplex is Europe's longest double-deck tunnel. The Community Chest of Hong Kong The Community Chest of Hong Kong ( Chinese : 香港公益金 ) is an independent, nonprofit organization established on 8 November 1968 in Hong Kong. The Community Chest serves as an umbrella organization to provide grants to
1152-505: Is intended to carry both the Istanbul metro and a two-level highway, over a length of 6.5 km (4.0 miles). The French A86 Duplex Tunnel [ fr ] in west Paris consists of two bored tunnel tubes, the eastern one of which has two levels for light motorized vehicles, over a length of 10 km (6.2 miles). Although each level offers a physical height of 2.54 m (8.3 ft), only traffic up to 2 m (6.6 ft) tall
1224-678: Is provided for the youth with collaborations of Hong Kong Air Cadet Corps and Boys' Brigade, Hong Kong , etc. Play-related services are also provided. Medical treatment is provided and community health care is also given out in the form of programmes such as health maintenance program and cancer education. Other services like recreational therapy and ambulance services are also provided. Community services, counselling and befriending services, services for street sleepers, employment services and volunteer services are provided in different communities in Hong Kong. "Dress Special Day" (公益服飾日, formerly named "Dress Casual Day" 公益金便服日), first launched in 1993,
1296-494: Is relatively long and narrow; the length is often much greater than twice the diameter , although similar shorter excavations can be constructed, such as cross passages between tunnels. The definition of what constitutes a tunnel can vary widely from source to source. For example, in the United Kingdom, a road tunnel is defined as "a subsurface highway structure enclosed for a length of 150 metres (490 ft) or more." In
1368-401: Is sometimes necessary during the excavation of a tunnel. They are usually circular and go straight down until they reach the level at which the tunnel is going to be built. A shaft normally has concrete walls and is usually built to be permanent. Once the access shafts are complete, TBMs are lowered to the bottom and excavation can start. Shafts are the main entrance in and out of the tunnel until
1440-515: Is that the open building pit is muted after tunnel construction; no roof is placed. Some tunnels are double-deck, for example, the two major segments of the San Francisco–Oakland Bay Bridge (completed in 1936) are linked by a 160-metre (540 ft) double-deck tunnel section through Yerba Buena Island , the largest-diameter bored tunnel in the world. At construction this was a combination bidirectional rail and truck pathway on
1512-698: Is the Siloam Tunnel , built in Jerusalem by the kings of Judah around the 8th century BC. Another tunnel excavated from both ends, maybe the second known, is the Tunnel of Eupalinos , which is a tunnel aqueduct 1,036 m (3,400 ft) long running through Mount Kastro in Samos , Greece. It was built in the 6th century BC to serve as an aqueduct . In Ethiopia , the Siqurto foot tunnel , hand-hewn in
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#17327904617901584-429: Is usually completely enclosed except for the two portals common at each end, though there may be access and ventilation openings at various points along the length. A pipeline differs significantly from a tunnel, though some recent tunnels have used immersed tube construction techniques rather than traditional tunnel boring methods. A tunnel may be for foot or vehicular road traffic , for rail traffic, or for
1656-569: The Balvano train disaster , was caused by a train stalling in the Armi tunnel in Italy in 1944, killing 426 passengers. Designers try to reduce these risks by installing emergency ventilation systems or isolated emergency escape tunnels parallel to the main passage. Government funds are often required for the creation of tunnels. When a tunnel is being planned or constructed, economics and politics play
1728-536: The Government of Hong Kong , is 1.2 kilometres (0.75 mi) long and has three lanes in either direction in the southern part of Tsing Yi from Sai Tso Wan to Nam Wan Kok . It provides linkage between the eastern part of the New Territories and Hong Kong International Airport . The tunnel is toll-free. The twin tunnels are 15 metres (49 ft) wide with 12 cross-passages and emergency walkways, and
1800-638: The Penny's Bay reclamation project or processed into aggregates at a local quarry. Spoil was taken away by a fleet of trucks, one leaving the site every 100 seconds during the working day from 8am to 7pm. Environmental measures taken to minimise noise and nuisance to road users and the public included: a 7.5m-tall noise barrier , and continuous monitoring to ensure noise and vibration limits are not exceeded during tunnel blasting; blast doors for any blasting conducted near roads; and 40 water sprinklers and washing facilities at all exits for vehicles to use before leaving
1872-471: The Port Authority of New York and New Jersey was not aware of this bill and had not asked for a grant for such a project. Increased taxes to finance a large project may cause opposition. Tunnels are dug in types of materials varying from soft clay to hard rock. The method of tunnel construction depends on such factors as the ground conditions, the groundwater conditions, the length and diameter of
1944-848: The Queens-Midtown Tunnel between Manhattan and the borough of Queens on Long Island ; the Detroit-Windsor Tunnel between Michigan and Ontario ; and the Elizabeth River tunnels between Norfolk and Portsmouth, Virginia ; the 1934 River Mersey road Queensway Tunnel ; the Western Scheldt Tunnel , Zeeland, Netherlands; and the North Shore Connector tunnel in Pittsburgh, Pennsylvania . The Sydney Harbour Tunnel
2016-472: The River Mersey at Liverpool was chosen over a massively high bridge partly for defense reasons; it was feared that aircraft could destroy a bridge in times of war, not merely impairing road traffic but blocking the river to navigation. Maintenance costs of a massive bridge to allow the world's largest ships to navigate under were considered higher than for a tunnel. Similar conclusions were reached for
2088-679: The United Kingdom of digging tunnels in strong clay-based soil structures. This method of cut and cover construction required relatively little disturbance of property during the renewal of the United Kingdom's then ancient sewerage systems. It was also used during the First World War by Royal Engineer tunnelling companies placing mines beneath German lines, because it was almost silent and so not susceptible to listening methods of detection. Tunnel boring machines (TBMs) and associated back-up systems are used to highly automate
2160-610: The canton of Glarus . The borehole has a diameter of 8.03 metres (26.3 ft). The four TBMs used for excavating the 57-kilometre (35 mi) Gotthard Base Tunnel , in Switzerland , had a diameter of about 9 metres (30 ft). A larger TBM was built to bore the Green Heart Tunnel (Dutch: Tunnel Groene Hart) as part of the HSL-Zuid in the Netherlands, with a diameter of 14.87 metres (48.8 ft). This in turn
2232-489: The water table . This pressurizes the ground ahead of the TBM cutter head to balance the water pressure. The operators work in normal air pressure behind the pressurized compartment, but may occasionally have to enter that compartment to renew or repair the cutters. This requires special precautions, such as local ground treatment or halting the TBM at a position free from water. Despite these difficulties, TBMs are now preferred over
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2304-415: The 10 km Run and 21 km Half Marathon to raise funds to designated services supported by The Community Chest. A major fund-raising programme providing a direct channel for corporations and employees to make donations. Total contribution from corporations and employees, raised through direct donations, self-organised fundraising events or CARE Scheme – monthly payroll deduction, are recognised through
2376-689: The 16th century as a metaphor for a narrow, confined space like the inside of a cask. Some of the earliest tunnels used by humans were paleoburrows excavated by prehistoric mammals. Much of the early technology of tunneling evolved from mining and military engineering . The etymology of the terms "mining" (for mineral extraction or for siege attacks ), " military engineering ", and " civil engineering " reveals these deep historic connections. Predecessors of modern tunnels were adits that transported water for irrigation , drinking, or sewerage . The first qanats are known from before 2000 BC. The earliest tunnel known to have been excavated from both ends
2448-638: The 1960s. The main idea of this method is to use the geological stress of the surrounding rock mass to stabilize the tunnel, by allowing a measured relaxation and stress reassignment into the surrounding rock to prevent full loads becoming imposed on the supports. Based on geotechnical measurements, an optimal cross section is computed. The excavation is protected by a layer of sprayed concrete, commonly referred to as shotcrete . Other support measures can include steel arches, rock bolts, and mesh. Technological developments in sprayed concrete technology have resulted in steel and polypropylene fibers being added to
2520-716: The 1971 Kingsway Tunnel under the Mersey. In Hampton Roads, Virginia , tunnels were chosen over bridges for strategic considerations; in the event of damage, bridges might prevent US Navy vessels from leaving Naval Station Norfolk . Water-crossing tunnels built instead of bridges include the Seikan Tunnel in Japan; the Holland Tunnel and Lincoln Tunnel between New Jersey and Manhattan in New York City ;
2592-655: The Campaign Committee, the Public Relations Committee and the Admissions, Budgets and Allocations Committee. Over 300 volunteers serving on various sub-committees contribute to support the work of these committees. They also work with the 40 staff at the Chest office to accomplish their fundraising target each year and allocate these funds to over 140 social welfare agencies. Each year, more than 1.7 million needy people benefit from
2664-483: The Chest" Television Show ( 萬眾同心公益金 ) is another major initiative. It is jointly produced by The Community Chest and Television Broadcast Limited. Local celebrities, prominent social elites and famous stars pitch in their efforts to rally support from the general public. There are many innovative and entertaining programmes rolled out to raise funds for the Chest's member social welfare agencies. Runners from Corporations and organisations pitched in their support by joining
2736-635: The Community Chest of Hong Kong. They are the visually impaired, the hearing impaired, the mentally handicapped, the physically handicapped, people who are chronically ill, drug-abusers, ex-offenders and people with other disabilities. In services provided to children and youth, provision of after school care services is one of the major parts. Also, youth counselling and recreational services are provided in youth centres. While collaborating with organisations like The Hong Kong Award for Young People and The Hong Kong Federation of Youth Groups , developmental and supportive services are provided. Furthermore, training
2808-709: The Middle Ages, crosses a mountain ridge. In the Gaza Strip , the network of tunnels was used by Jewish strategists as rock-cut shelters, in first links to Judean resistance against Roman rule in the Bar Kokhba revolt during the 2nd century AD. A major tunnel project must start with a comprehensive investigation of ground conditions by collecting samples from boreholes and by other geophysical techniques. An informed choice can then be made of machinery and methods for excavation and ground support, which will reduce
2880-599: The United States, the NFPA definition of a tunnel is "An underground structure with a design length greater than 23 m (75 ft) and a diameter greater than 1,800 millimetres (5.9 ft)." The word "tunnel" comes from the Middle English tonnelle , meaning "a net", derived from Old French tonnel , a diminutive of tonne ("cask"). The modern meaning, referring to an underground passageway, evolved in
2952-400: The blocky nature of rocks, the exact location of fault zones, or the stand-up times of softer ground. This may be a particular concern in large-diameter tunnels. To give more information, a pilot tunnel (or "drift tunnel") may be driven ahead of the main excavation. This smaller tunnel is less likely to collapse catastrophically should unexpected conditions be met, and it can be incorporated into
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3024-502: The concrete mix to improve lining strength. This creates a natural load-bearing ring, which minimizes the rock's deformation . By special monitoring the NATM method is flexible, even at surprising changes of the geomechanical rock consistency during the tunneling work. The measured rock properties lead to appropriate tools for tunnel strengthening . In pipe jacking , hydraulic jacks are used to push specially made pipes through
3096-555: The construction site. Arup Group were the designers of the tunnel and a joint venture of Gammon Construction and Skanska were the main construction contractors (contract was awarded in January 2003). The contract also covered construction of tunnel control buildings and the 1.4 kilometres (0.87 mi) dual three-lane West Tsing Yi Viaduct. The cost for the tunnel has been estimated at HK$ 470m (civil works) and HK$ 83 million (electrical and mechanical systems). Fläkt Woods provided
3168-429: The drill/blast method. Temporary support for the tunnels have been provided by rock-bolts. Permanent supports have been provided by a concrete lining of varying thickness depending upon the stability of the ground. Three main types of support have been used: 400mm un-reinforced, 500mm un-reinforced, and 600mm reinforced. Nearly all of the 550,000 cubic metres (19,000,000 cu ft) of tunnel spoil will be reused in
3240-490: The elderly in Hong Kong. For child welfare services, there are day care services, developmental and supportive services, residential child care services and child protection services. For family welfare services, there are 5 components: family support services, services for families with special needs, services for family reunion and new arrivals, services for women/men as well as parent education. Eight groups of people are provided with aftercare and rehabilitation services from
3312-409: The entire tunnelling process, reducing tunnelling costs. In certain predominantly urban applications, tunnel boring is viewed as a quick and cost-effective alternative to laying surface rails and roads. Expensive compulsory purchase of buildings and land, with potentially lengthy planning inquiries, is eliminated. Disadvantages of TBMs arise from their usually large size – the difficulty of transporting
3384-531: The fans continuously to self-destruct, to prove their capability of withstanding temperatures of up to 400 °C for one hour. The fans incorporated guide vanes for flow straightening to achieve maximum performance and ran at 995 RPM. In the preliminary design phase of the tunnel, COWI established an overall concept for the electrical and mechanical systems with emphasis on safety-related functions such as electric power supply, tunnel lighting, fire fighting, tunnel ventilation and smoke extraction. This overall concept
3456-441: The final tunnel or used as a backup or emergency escape passage. Alternatively, horizontal boreholes may sometimes be drilled ahead of the advancing tunnel face. Other key geotechnical factors: For water crossings, a tunnel is generally more costly to construct than a bridge. However, both navigational and traffic considerations may limit the use of high bridges or drawbridges intersecting with shipping channels, necessitating
3528-711: The fundraising programs organized by the Chest. The Chest's administrative costs are subsidized by an annual grant from The Hong Kong Jockey Club , and by returns on investments. Therefore, the Chest is able to allocate 100% of the donations it receives to the beneficiaries without any deduction for administrative expenses. There are over 168 member agencies of the Chest in 2023. They are: (Agency names are listed in alphabetical order) There are residential services, community support services, carer support services, and empowerment and health services. The Community Chest of Hong Kong collaborates with its member agencies such as Helping Hand and Caritas Hong Kong , to provide services for
3600-405: The ground behind a TBM or shield. This method is commonly used to create tunnels under existing structures, such as roads or railways. Tunnels constructed by pipe jacking are normally small diameter bores with a maximum size of around 3.2 metres (10 ft). Box jacking is similar to pipe jacking, but instead of jacking tubes, a box-shaped tunnel is used. Jacked boxes can be a much larger span than
3672-640: The immersed-tube type), while deep tunnels are excavated, often using a tunnelling shield . For intermediate levels, both methods are possible. Large cut-and-cover boxes are often used for underground metro stations, such as Canary Wharf tube station in London. This construction form generally has two levels, which allows economical arrangements for ticket hall, station platforms, passenger access and emergency egress, ventilation and smoke control, staff rooms, and equipment rooms. The interior of Canary Wharf station has been likened to an underground cathedral, owing to
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#17327904617903744-435: The inevitable smoke and steam. A major disadvantage of cut-and-cover is the widespread disruption generated at the surface level during construction. This, and the availability of electric traction, brought about London Underground's switch to bored tunnels at a deeper level towards the end of the 19th century. Prior to the replacement of manual excavation by the use of boring machines, Victorian tunnel excavators developed
3816-468: The large TBM to the site of tunnel construction, or (alternatively) the high cost of assembling the TBM on-site, often within the confines of the tunnel being constructed. There are a variety of TBM designs that can operate in a variety of conditions, from hard rock to soft water-bearing ground. Some TBMs, the bentonite slurry and earth-pressure balance types, have pressurized compartments at the front end, allowing them to be used in difficult conditions below
3888-418: The local social welfare services. In lieu of gifts to celebrate birthdays, weddings, anniversaries, opening for new businesses and other special occasions, donors can share their happiness with the needy by donating to the Chest through this year-round programme. "Greening for the Chest", jointly organised by The Community Chest and Education Bureau, aims to convey the message of environmental protection among
3960-629: The lower deck with automobiles above, now converted to one-way road vehicle traffic on each deck. In Turkey, the Eurasia Tunnel under the Bosphorus , opened in 2016, has at its core a 5.4 km (3.4 miles) two-deck road tunnel with two lanes on each deck. Additionally, in 2015 the Turkish government announced that it will build three -level tunnel, also under the Bosporus. The tunnel
4032-483: The older method of tunnelling in compressed air, with an airlock/decompression chamber some way back from the TBM, which required operators to work in high pressure and go through decompression procedures at the end of their shifts, much like deep-sea divers . In February 2010, Aker Wirth delivered a TBM to Switzerland, for the expansion of the Linth–Limmern Power Stations located south of Linthal in
4104-540: The operation of empty and loaded trains at the same time. The temporary way is replaced by the permanent way at completion, thus explaining the term " Perway ". The vehicles or traffic using a tunnel can outgrow it, requiring replacement or enlargement: An open building pit consists of a horizontal and a vertical boundary that keeps groundwater and soil out of the pit. There are several potential alternatives and combinations for (horizontal and vertical) building pit boundaries. The most important difference with cut-and-cover
4176-522: The project is completed. If a tunnel is going to be long, multiple shafts at various locations may be bored so that entrance to the tunnel is closer to the unexcavated area. Once construction is complete, construction access shafts are often used as ventilation shafts , and may also be used as emergency exits. The New Austrian Tunnelling method (NATM)—also referred to as the Sequential Excavation Method (SEM) —was developed in
4248-490: The proper machinery must be selected. Large infrastructure projects require millions or even billions of dollars, involving long-term financing, usually through issuance of bonds . The costs and benefits for an infrastructure such as a tunnel must be identified. Political disputes can occur, as in 2005 when the US House of Representatives approved a $ 100 million federal grant to build a tunnel under New York Harbor. However,
4320-482: The risk of encountering unforeseen ground conditions. In planning the route, the horizontal and vertical alignments can be selected to make use of the best ground and water conditions. It is common practice to locate a tunnel deeper than otherwise would be required, in order to excavate through solid rock or other material that is easier to support during construction. Conventional desk and preliminary site studies may yield insufficient information to assess such factors as
4392-441: The same time, raise funds for the needy. Participants are encouraged to solicit sponsorship to perform their own "GREEN" acts to support the event. This event is held to encourage people to donate their lunch fees to support the needy. Each donor will be given a Skip Lunch Day Coupon by making a donation of HK$ 30 or more. In 2010, this event was supported by nearly 300 organisations and government departments. Over HK$ 1.6 million
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#17327904617904464-542: The sheer size of the excavation. This contrasts with many traditional stations on London Underground , where bored tunnels were used for stations and passenger access. Nevertheless, the original parts of the London Underground network, the Metropolitan and District Railways, were constructed using cut-and-cover. These lines pre-dated electric traction and the proximity to the surface was useful to ventilate
4536-551: The significant contributions from schools participating in "Gold Flag Sale", the event has helped raise a generous amount of resources. In campaign year 2008/2009, The Community Chest has raised a total of 18,005,080 Hong Kong Dollars. In 2009/2010, The Community Chest allocated over HK$ 180 million to its member agencies: 32% on Rehabilitation and Aftercare Services, 15% on Children and Youth Services, 10% on Elderly Services, 19% on Community Development and Other Services, 18% on Family and Child Welfare Services, and also used 6% of
4608-400: The tunnel drive, the depth of the tunnel, the logistics of supporting the tunnel excavation, the final use and the shape of the tunnel and appropriate risk management. There are three basic types of tunnel construction in common use. Cut-and-cover tunnels are constructed in a shallow trench and then covered over. Bored tunnels are constructed in situ, without removing the ground above. Finally,
4680-428: The two most common being bored tunnels or immersed tubes , examples are Bjørvika Tunnel and Marmaray . Submerged floating tunnels are a novel approach under consideration; however, no such tunnels have been constructed to date. During construction of a tunnel it is often convenient to install a temporary railway, particularly to remove excavated spoil , often narrow gauge so that it can be double track to allow
4752-513: The ventilation system for the tunnel. COWI has provided specialist assistance to Ove Arup and Partners with the design of electrical and mechanical systems for the Nam Wan Tunnel and two adjoining viaducts. Fläkt Woods provided the ventilation solutions by supplying three immense fans for the tunnel. The axial flow fans measured 2.65 m in diameter, were powered by 900 kW motors and ran at pressures of 3,800 Pa. Fläkt Woods ran one of
4824-426: The youth. Over the years, students from the 18 Districts Community Youth Clubs have been encouraged to take part in cleaning, planting and tree tendering in country parks, and at the same time, raise funds for the needy in Hong Kong. With the assistance from Leisure and Cultural Services Department and Agriculture, Fisheries and Conservation Department, organisations could also clean or plant at designated locations for
4896-575: Was constructed to provide a second harbour crossing and to alleviate traffic congestion on the Sydney Harbour Bridge , without spoiling the iconic view. Other reasons for choosing a tunnel instead of a bridge include avoiding difficulties with tides, weather, and shipping during construction (as in the 51.5-kilometre or 32.0-mile Channel Tunnel ), aesthetic reasons (preserving the above-ground view, landscape, and scenery), and also for weight capacity reasons (it may be more feasible to build
4968-451: Was raised. Hong Kong Exchanges and Clearing Limited (HKEx) has always been a staunch partner of The Community Chest of Hong Kong. To encourage listed companies to re-invest into the local community, HKEx has initiated "Stock Code Balloting for Charity Scheme" in 1999 to give each company listing on Stock Exchange of Hong Kong the option to choose its stock code by making a donation to The Community Chest and help channel invaluable resources to
5040-716: Was renamed "Dress Special Day" in 2006. In doing so, the theme of this activity can be more flexible and vivid. It is hoped that donation can reach a higher peak by drawing strength from more participants. Website for the year 2009 "Walks for Millions" ( 公益金百萬行 ) is a flagship fund-raising event of the Community Chest. It was first launched in 1971. People can participate in the walk by soliciting donation from friends and relatives. A number of walks were organised at major infrastructures before their official opening to public use. Until campaign year 2009/2010, over 3 million participants have joined this meaningful event and 160 walks have been organised by The Community Chest. "Community for
5112-732: Was superseded by the Madrid M30 ringroad , Spain, and the Chong Ming tunnels in Shanghai , China. All of these machines were built at least partly by Herrenknecht . As of August 2013 , the world's largest TBM was " Big Bertha ", a 17.5-metre (57.5 ft) diameter machine built by Hitachi Zosen Corporation , which dug the Alaskan Way Viaduct replacement tunnel in Seattle, Washington (US). A temporary access shaft
5184-872: Was used as a basis for the detailed design. Later in the project COWI, reviewed the client's detailed design of electrical and mechanical systems. The electrical and mechanical systems included the following: medium- and low-voltage distribution (11 kV/0.4 kV); reliable power supply based on UPS and diesel generators; tunnel lighting and road lighting; lighting in portal buildings, technical rooms and cross passages between tunnels; Central Monitoring and Control System (CMCS); fire detection system; public mobile communication system; fire fighting equipment, including fire water booster pumps, hydrants and portable extinguishers; tunnel ventilation for normal operation, congested operation and emergency situations (smoke control); smoke extraction system; pressurised air supply; HVAC and plumbing in portal buildings. Prior to its formal commissioning,
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