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Harbor Tunnel

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50-876: (Redirected from Harbour Tunnel ) Harbour Tunnel or Harbor Tunnel may refer to: Australia [ edit ] Sydney Harbour Tunnel , New South Wales Western Harbour Tunnel , New South Wales Hong Kong [ edit ] Cross-Harbour Tunnel , Hong Kong United States [ edit ] Baltimore Harbor Tunnel and associated Harbor Tunnel Thruway , Maryland Cross-Harbor Rail Tunnel in New York Harbor between New York and New Jersey Ted Williams Tunnel (also known as Third Harbor Tunnel ) in Boston Harbor, Massachusetts See also [ edit ] Harbour Bridge (disambiguation) Harbour Crossing (disambiguation) Topics referred to by

100-556: A "thermal bridge" that degrades thermal performance. Also, since steel does not have the same thermal expansion coefficient as concrete, as the wall heats and cools any steel that is not embedded in the concrete can create thermal stresses that cause cracking and spalling. To achieve better thermal performance, insulation was added in the void, and in many applications today the steel trusses have been replaced by composite (fibreglass, plastic, etc.) connection systems. These systems, which are specially developed for this purpose, also eliminate

150-517: A 50/50 joint venture company which constructed the tunnel under contract; with a 30-year operating contract, including revenue collection and maintenance, from 1992 until 2022. As a result of the 1997 separation of assets of Transfield and the creation of the Tenix group (owned by Olbia), the ongoing 30-year operating contract for management of the tunnel was split between Kumagai Gumi (50%), Transfield (25%) and Olbia (25%). The total construction cost of

200-482: A building facade or erect free-standing walls for landscaping, soundproofing , and security. In appropriate instances precast products – such as beams for bridges, highways, and parking structure decks – can be prestressed structural elements. Stormwater drainage, water and sewage pipes, and tunnels also make use of precast concrete units. Precast concrete molds can be made of timber, steel, plastic, rubber, fiberglass, or other synthetic materials, with each giving

250-668: A building's enclosure or "envelope," they can be designed to also serve as part of the building's structural system, eliminating the need for beams and columns on the building perimeter. Besides their energy efficiency and aesthetic versatility, they also provide excellent noise attenuation, outstanding durability (resistant to rot, mold, etc.), and rapid construction. In addition to the good insulation properties, sandwich panels require fewer work phases to complete. Compared to double-walls, for example, which have to be insulated and filled with concrete on site, sandwich panels require much less labor and scaffolding. The precast concrete industry

300-432: A controlled environment (typically referred to as a precast plant), the precast concrete is afforded the opportunity to properly cure and be closely monitored by plant employees. Using a precast concrete system offers many potential advantages over onsite casting. Precast concrete production can be performed on ground level, which maximizes safety in its casting. There is greater control over material quality and workmanship in

350-414: A precast plant compared to a construction site. The forms used in a precast plant can be reused hundreds to thousands of times before they have to be replaced, often making it cheaper than onsite casting in terms of cost per unit of formwork. Precast concrete forming systems for architectural applications differ in size, function, and cost. Precast architectural panels are also used to clad all or part of

400-459: A unique finish. In addition, many surface finishes for the four precast wall panel types – sandwich, plastered sandwich, inner layer and cladding panels – are available, including those creating the looks of horizontal boards and ashlar stone . Color may be added to the concrete mix, and the proportions and size aggregate also affect the appearance and texture of finished concrete surfaces. Ancient Roman builders made use of concrete and soon poured

450-436: A varying toll (that was introduced in 2009) of between $ 2.50 and $ 4.00, depending on the time of day. The toll is levied on the southbound approach to the tunnel entrance. Until July 2022 it was unannounced whether tolls would continue after the transfer of ownership to the state government on 1 September 2022. It was eventually announced by the state government that the toll would continue, to be used for maintenance just like

500-421: Is a construction product produced by casting concrete in a reusable mold or "form" which is then cured in a controlled environment, transported to the construction site and maneuvered into place; examples include precast beams , and wall panels, floors, roofs, and piles. In contrast, cast-in-place concrete is poured into site-specific forms and cured on site. Recently lightweight expanded polystyrene foam

550-477: Is a huge energy consuming industry, and precast concrete products are and will continue to be more energy efficient than its counterparts. The wide range of designs, colours, and structural options that these products provide is also making it a favourable choice for its consumers. Many state and federal transportation projects in the United States require precast concrete suppliers to be certified by either

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600-426: Is also used for the roll ways of some rubber-tyred metros . Modular paving is available in a rainbow of colors, shapes, sizes, and textures. These versatile precast concrete pieces can be designed to mimic brick, stone or wood. Underground vaults or mausoleums require watertight structures that withstand natural forces for extended periods of time. Storage of hazardous material, whether short-term or long-term,

650-407: Is an increasingly important environmental issue, calling for containers that not only seal in the materials, but are strong enough to stand up to natural disasters or terrorist attacks. Seawalls , floating docks, underwater infrastructure, decking, railings, and a host of amenities are among the uses of precast along the waterfront. When designed with heavy weight in mind, precast products counteract

700-501: Is being used as the cores of precast wall panels, saving weight and increasing thermal insulation . Precast stone is distinguished from precast concrete by the finer aggregate used in the mixture, so the result approaches the natural product. Precast concrete is employed in both interior and exterior applications, from highway, bridge, and high-rise projects to parking structures, K-12 schools, warehouses, mixed-use, and industrial building construction. By producing precast concrete in

750-610: Is different from Wikidata All article disambiguation pages All disambiguation pages Sydney Harbour Tunnel The Sydney Harbour Tunnel is a twin-tube road tunnel in Sydney, Australia. The tunnel was completed and opened to traffic in August 1992 to provide a second vehicular crossing of Sydney Harbour to alleviate congestion on the Sydney Harbour Bridge . It is one of two transportation tunnels under

800-701: Is essential that each structural component be designed and tested to withstand both the tensile and compressive loads that the member will be subjected to over its lifespan. Expanded polystyrene cores are now in precast concrete panels for structural use, making them lighter and serving as thermal insulation. Multi-storey car parks are commonly constructed using precast concrete. The constructions involve putting together precast parking parts which are multi-storey structural wall panels, interior and exterior columns, structural floors, girders, wall panels, stairs, and slabs. These parts can be large; for example, double-tee structural floor modules need to be lifted into place with

850-459: Is largely dominated by Government initiated projects for infrastructural development. However, these are also being extensively used for residential (low and high rise) and commercial constructions because of their various favourable attributes. The efficiency, durability, ease, cost effectiveness, and sustainable properties of these products have brought a revolutionary shift in the time consumed in construction of any structure. Construction industry

900-410: Is the most common form of concrete reinforcement. It is typically made from steel, manufactured with ribbing to bond with concrete as it cures. Rebar is versatile enough to be bent or assembled to support the shape of any concrete structure. Carbon steel is the most common rebar material. However, stainless steel, galvanized steel, and epoxy coatings can prevent corrosion. The following is a sampling of

950-460: Is typically 8 inches, but their designs are often customized to the application. In a typical 8-inch wall panel the concrete wythes are each 2-3/8 inches thick), sandwiching 3-1/4 inches of high R-value insulating foam. The interior and exterior wythes of concrete are held together (through the insulation) with some form of connecting system that is able to provide the needed structural integrity. Sandwich wall panels can be fabricated to

1000-709: The Sydney Orbital Network would cease by 2010. The Sydney Harbour Tunnel went fully electronic in July 2007 with both e-TAG and e-pass video tolling arrangements in use, similar to technologies used by the Westlink M7 , Cross City Tunnel and the Lane Cove Tunnel . This measure has substantially eased the traffic jams heading towards the electronic gantries, and providing increased convenience and time savings. The Sydney Harbour Tunnel attracts

1050-459: The IMTs were lowered into the trench by a system of pontoons and control towers. After the IMTs were in place, the trenches were backfilled and then a rock armour was placed over the top to protect the units against marine hazards, such as anchors or sinking vessels. The land tunnels were constructed by a combination of driving and cut-and-cover techniques , designed to be strong enough to withstand

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1100-644: The Jim Bridger Building in Williston, North Dakota, was precast in Minnesota with air, electrical, water, and fiber utilities preinstalled into the building panels. The panels were transported over 800 miles to the Bakken oilfields, and the commercial building was assembled by three workers in minimal time. The building houses over 40,000 square feet of shops and offices. Virtually the entire building

1150-634: The Sydney Harbour Bridge. Tolls will rise in October 2023 for the first time in 14 years. The tunnel was opened to the public to walk through from North Sydney (Falcon Street) to Eastern Sydney (The Domain) on 30 August 1992. The proceeds of the tickets sold for this event were donated to the Royal Institute for Deaf and Blind Children . The tunnel opened to traffic on 31 August 1992. Precast concrete Precast concrete

1200-703: The UK for a variety of applications including agricultural buildings, grain stores, silage clamps, slurry stores, livestock walling and general retaining walls. Panels can be used horizontally and placed either inside the webbings of RSJs ( I-beam ) or in front of them. Alternatively panels can be cast into a concrete foundation and used as a cantilever retaining wall. Precast concrete building components and site amenities are used architecturally as fireplace mantels, cladding, trim products, accessories and curtain walls. Structural applications of precast concrete include foundations, beams, floors, walls and other structural components. It

1250-461: The buoyant forces of water significantly better than most materials. Prestressing is a technique of introducing stresses into a structural member during fabrication and/or construction to improve its strength and performance. This technique is often employed in concrete beams, columns, spandrels, single and double tees, wall panels, segmental bridge units, bulb-tee girders, I-beam girders, and others. Many projects find that prestressed concrete provides

1300-481: The construction, safety, and site protection of roads, airports, and railroad transportation systems. Products include: box culverts , 3-sided culverts, bridge systems, railroad crossings, railroad ties, sound walls /barriers, Jersey barriers , tunnel segments, concrete barriers, TVCBs, central reservation barriers, bollards, and other transportation products. Precast concrete can also be used to make underpasses, surface crossings, and pedestrian subways. Precast concrete

1350-408: The differential thermal expansion problem. The best thermal performance is achieved when the insulation is continuous throughout the wall section, i.e., the wythes are thermally separated completely to the ends of the panel. Using continuous insulation and modern composite connection systems, R-values up to R-28.2 can be achieved. The overall thickness of sandwich wall panels in commercial applications

1400-507: The fans was one of the most comprehensive ever, covering flowrate and pressure, power measurements, sound levels, bearing vibration, x-raying of all impeller components, high-temperature tests at 200 °C (392 °F) for two hours, impeller strain, and 24-hour run tests for reversals. The Harbour Tunnel was a partnership between the New South Wales government and private investors by tender. Transfield and Kumagai Gumi formed

1450-657: The harbour, the other being a set of rail tunnels for the Sydney Metro . The tunnel joins the Warringah Freeway at North Sydney and the Cahill Expressway at the entrance to the Domain Tunnel. It has two lanes in each direction, and runs at an angle of approximately thirty degrees (north to south) to the Sydney Harbour Bridge, which has eight lanes, with a tidal flow operation. In 2017,

1500-433: The help of precast concrete lifting anchor systems . Precast concrete is employed in a wide range of engineered earth retaining systems. Products include commercial and residential retaining walls , sea walls , mechanically stabilized earth panels, and other modular block systems. Sanitary and stormwater management products are structures designed for underground installation that have been specifically engineered for

1550-605: The impact of earthquakes. The northern end pylons of the Sydney Harbour Bridge were altered to allow for air exhaust from the tunnel to rise over the harbour. Bradfield Park on the northern side of the bridge also has air intakes. Fresh air is drawn by an underground ventilation station on the north shore and is pumped to all sections of the tunnel through vented ducts. The air supply uses fourteen axial flow fans, each up to 2.5 metres (8 ft 2 in) in diameter. The exhaust uses sixteen (eight in each northern pylon tower) fans that draw exhaust air through two underground ducts from

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1600-407: The length and width desired, within practical limits dictated by the fabrication system, the stresses of lifting and handling, and shipping constraints. Panels of 9-foot clear height are common, but heights up to 12 feet can be found. The fabrication process for precast concrete sandwich wall panels allows them to be produced with finished surfaces on both sides. Such finishes can be very smooth, with

1650-452: The lowest overall cost, considering production and lifetime maintenance. The precast concrete double-wall panel has been in use in Europe for decades. The original double-wall design consisted of two wythes of reinforced concrete separated by an interior void, held together with embedded steel trusses. With recent concerns about energy use, it is recognized that using steel trusses creates

1700-552: The material into moulds to build their complex network of aqueducts , culverts , and tunnels. Modern uses for pre-cast technology include a variety of architectural and structural applications – including individual parts, or even entire building systems. In the modern world, precast panelled buildings were pioneered in Liverpool , England , in 1905. The process was invented by city engineer John Alexander Brodie . The tram stables at Walton in Liverpool followed in 1906. The idea

1750-606: The numerous products that utilize precast/prestressed concrete. While this is not a complete list, the majority of precast/prestressed products typically fall under one or Since precast concrete products can withstand the most extreme weather conditions and will hold up for many decades of constant usage they have wide applications in agriculture. These include bunker silos, cattle feed bunks, cattle grid , agricultural fencing, H-bunks, J-bunks, livestock slats, livestock watering trough, feed troughs, concrete panels, slurry channels, and more. Prestressed concrete panels are widely used in

1800-575: The panels to reduce on-site construction time. The carpenters, electricians and plumbers do need to make some slight adjustments when first becoming familiar with some of the unique aspects of the wall panels. However, they still perform most of their job duties in the manner to which they are accustomed. Precast concrete sandwich wall panels have been used on virtually every type of building, including schools, office buildings, apartment buildings, townhouses, condominiums, hotels, motels, dormitories, and single-family homes. Although typically considered part of

1850-702: The precast concrete products industry produces utility, underground, and other non-prestressed products, and is represented primarily by the National Precast Concrete Association (NPCA). In Australia , The New South Wales Government Railways made extensive use of precast concrete construction for its stations and similar buildings. Between 1917 and 1932, it erected 145 such buildings. Beyond cladding panels and structural elements, entire buildings can be assembled from precast concrete. Precast assembly enables fast completion of commercial shops and offices with minimal labor. For example,

1900-511: The project was $ 554 million. $ 223 million of this was an interest-free loan from the NSW Government, to be repaid at the conclusion of the operating contract in August 2022 when the tunnel would be transferred to public ownership. The government had also guaranteed an Ensured Revenue Stream (ERS) to the operator, whereby it makes up the shortfall between toll collections and the guaranteed amount. As toll revenues have been below

1950-489: The projected amount, in 2008 for example, the government paid the operator $ 58.9 million, with the total amount forecast to be $ 1.1 billion from 2008 to 2022. The NSW Auditor-General had also raised concerns that the tunnel's expenses may make the operating company default on the $ 223 million loan, however the government remained confident in it. With the 30-year operating contract about to expire, in April 2022,

2000-405: The purpose of further processing into non-contaminating liquids and soil products. Products include: aeration systems , distribution boxes, dosing tanks, dry wells , grease interceptors , leaching pits, sand-oil/oil-water interceptors, septic tanks , water/sewage storage tanks, wet wells, fire cisterns, and other water and wastewater products. Precast concrete transportation products are used in

2050-423: The same term [REDACTED] This disambiguation page lists articles associated with the title Harbor Tunnel . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Harbor_Tunnel&oldid=1190828316 " Category : Disambiguation pages Hidden categories: Short description

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2100-403: The southern entrance to its deepest point, 25 metres (82 ft) below sea level. The construction was undertaken by Thiess Contractors . The IMT structure consists of eight precast concrete units. The units were constructed over 100 kilometres (62 mi) away in a casting basin at Port Kembla and then towed to Sydney Harbour . A trench was dredged before the arrival of the IMTs and then

2150-485: The state government signed a 15-year contract with Ventia for the asset management, operations and maintenance of the Sydney Harbour Tunnel as well as the under-construction Western Harbour Tunnel . Tolling arrangements were unrelated to the new agreement. On 1 September 2022, the tunnel reverted back to state government ownership. In 2006 the New South Wales government announced that all cash tolls on

2200-446: The surfaces painted, stained, or left natural; for interior surfaces, the finish is comparable to drywall in smoothness and can be finished using the same prime and paint procedure as is common for conventional drywall construction. If desired, the concrete can be given an architectural finish, where the concrete itself is colored and/or textured. Colors and textures can provide the appearance of brick, stone, wood, or other patterns through

2250-795: The treatment and removal of pollutants from sanitary and stormwater run-off. These precast concrete products include stormwater detention vaults , catch basins , and manholes . For communications, electrical, gas or steam systems, precast concrete utility structures protect the vital connections and controls for utility distribution. Precast concrete is nontoxic and environmentally safe. Products include: hand holes, hollow-core products, light pole bases, meter boxes, panel vaults, pull boxes, telecommunications structures, transformer pads, transformer vaults, trenches, utility buildings, utility vaults , utility poles, controlled environment vaults (CEVs), and other utility structures. Precast water and wastewater products hold or contain water, oil or other liquids for

2300-423: The tunnel ventilation station and transfer the air to the top of the pylon. They can expel it at up to 1,500 m /s (53,000 cu ft/s) – equivalent to changing all the air in the tunnel every two minutes with the capability of running in reverse in an emergency and all fans are rated for smoke extraction. Each of the fans has a duty of 53 to 103 m /s (1,900 to 3,600 cu ft/s). The testing of

2350-405: The tunnel was carrying around 96,000 vehicles per day. The tunnel is made up of three sections: twin 900-metre (3,000 ft) land tunnels on the north shore, twin 400-metre (1,300 ft) land tunnels on the south shore and a 960-metre (3,150 ft) immersed tube (IMT) structure. The tunnel falls about 55 metres (180 ft) from the northern entrance and about 35 metres (115 ft) from

2400-504: The use of reusable formliners , or, in the most sophisticated applications, actual brick, stone, glass, or other materials can be cast into the concrete surface. Window and door openings are cast into the walls at the manufacturing plant as part of the fabrication process. In many applications, electrical and telecommunications conduit and boxes are cast directly into the panels in the specified locations. In some applications, utilities, plumbing and even heating components have been cast into

2450-492: Was fabricated in Minnesota. Reinforcing concrete with steel improves strength and durability. On its own, concrete has good compressive strength, but lacks tensile and shear strength and can be subject to cracking when bearing loads for long periods of time. Steel offers high tensile and shear strength to make up for what concrete lacks. Steel behaves similarly to concrete in changing environments, which means it will shrink and expand with concrete, helping avoid cracking. Rebar

2500-955: Was not taken up extensively in Britain. However, it was adopted all over the world, particularly in Central and Eastern Europe as well as in Million Programme in Scandinavia. In the US, precast concrete has evolved as two sub-industries, each represented by a major association. The precast concrete structures industry, represented primarily by of the Precast/Prestressed Concrete Institute (PCI), focuses on prestressed concrete elements and on other precast concrete elements used in above-ground structures such as buildings, parking structures, and bridges, while

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