2013年12月11日星期三

Famous bridges in China

Shanghai Yangtze River Bridge

The Shanghai Yangtze River Bridge starts at the tunnel exit, crosses Changxing Island at ground level, then crosses to Chongming Island, ending at Chenjia Town.

It consists of two long viaducts with a higher cable-stayed section in the middle to allow the passage of ships. The total length is 16.63 kilometres (10.33 mi), of which 6.66 kilometres (4.14 mi) is road and 9.97 kilometres (6.20 mi) bridge. The overall shape of the bridge is not linear but slightly sigmoid ("S" shaped).

The central cable-stayed span is about 730 metres (2,395 ft), the longest span of any bridge in Shanghai, and the tenth longest cable-stayed span in the world.[4] The span arrangement is 92+258+730+258+72 m.[5]

The bridge has three road lanes in each direction, with a designed speed of 100 kilometres per hour (62 mph). Room on both flanks of the bridge is reserved for a future metro line, so total deck width is 35.3 m (115.8 ft).

Shanghai Yangtze River Tunnel

Tunnel starts on the south bank of the Yangtze at Wuhaogou, Pudong and ends in the south of Changxing Island. It is 8.9 kilometres (5.5 mi) in length,[1] and has two stacked levels. The upper level is for a motorway, and has three lanes in each direction, with a designed speed of 80 kilometres per hour (50 mph). The lower level is reserved for a future Shanghai Metro line.

The tunnelling was completed using two of the largest tunnel boring machines (TBMs) ever built. The TBMs were 15.43 metres (50.6 ft) in diameter, 135 metres (443 ft) long, and weighed 2,300t.

Sutong Bridge

With a span of 1,088 metres (3,570 ft), it was the cable-stayed bridge with the longest main span in the world in 2008-2012. Its two side spans are 300 metres (980 ft) each, and there are also four small cable spans. The bridge received the 2010 Outstanding Civil Engineering Achievement award (OCEA) from the American Society of Civil Engineers.

Two towers of the bridge are 306 metres (1,004 ft) high and thus the second tallest in the world. The total bridge length is 8,206 metres (26,923 ft). Construction began in June 2003, and the bridge was linked up in June 2007. The bridge was opened to traffic on 25 May 2008[3] and was officially opened on 30 June 2008. Construction has been estimated to cost about US$1.7 billion.

The completion of the bridge shortens the commute between Shanghai and Nantong, previously a four-hour ferry ride, to about an hour. It brings Nantong one step closer to becoming an important part of the Yangtze River Delta economic zone, and has further attracted foreign investors into the city. The bridge is also pivotal in the development of poorer northern Jiangsu regions.

The tower is an inverted Y-shaped reinforced concrete structure with one connecting girder between tower legs. The bridge deck is a steel box girder with internal transverse and longitudinal diaphragms and fairing noses at both sides of the bridge deck. The total width of the bridge deck is 41 metres including the fairing noses.

AECOM provided comprehensive services to the main contractor, China Harbour Engineering Co. Second Navigational Engineering Bureau in the construction phase of the bridge. The services include contractor's alternative design; development of construction methodology; construction engineering/erection analysis/geometry control; deck lifting methods and procedures; surveying and monitoring techniques and systems; stay cable installation simulations; advice on construction method statements and specifications; bridge aerodynamics and wind tunnel testing; vibration mitigation measures/devices; falsework and plant/equipment design; advice on innovation and high-technology and research and development.

Jiangyin Bridge

The Jiangyin Bridge is a suspension Bridge over the Yangtze River in Jiangsu, China. When it was completed it was the most seaward crossing of the Yangtze River however the Sutong Bridge and the Shanghai Yangtze River Tunnel and Bridge have since been built further downstream. The bridge has a main span of 1,385 metres (4,544 ft) connecting Jiangyin south of the river to Jingjiang to the north. When it was completed in 1999 it was the fourth longest suspension bridge span in the world and the longest in China. Several longer bridges have since been completed in china and abroad but it still ranks among the ten longest bridge spans in the world.

Taizhou Bridge

The Taizhou Bridge is a bridge in over the Yangtze River in Taizhou, Jiangsu, China. It is the longest double span suspension bridge in the world with two main spans of 1080m.

It won the 2013 Institution of Structural Engineers Supreme Award for structural engineering.

Second Nanjing Yangtze Bridge

The Second Nanjing Yangtze Bridge is a cable-stayed bridge over the Yangtze River in Nanjing, China. The bridge spans 628 metres (2,060 ft) carrying traffic on the G36 Nanjing–Luoyang Expressway. When it was copleted it was the third longest cable-stayed span in the world. As of 2013 it is still among the 20 longest spans. The bridge crosses from the Qixia District in south-east of the river over to Bagua Island.

Third Nanjing Yangtze Bridge

The Third Nanjing Yangtze Bridge is a cable-stayed bridge located in Nanjing, China. It is the third crossing of the Yangtze River at Nanjing. The cable-stayed portion is just a part of the 4.7 kilometers of the complete bridge. Constructed in slightly more than two years at a cost of $490 million, this bridge features dual 215 meters towers. The main span measures 648 meters. When it was completed in 2005 it was the third longest cable stayed span in the world.It still ranks among the top 20. The bridge carries the G42 Shanghai–Chengdu Expressway and the G2501 Nanjing Ring Expressway

2013年12月5日星期四

A look back and forward at Steel Bridge construction

How many do you konw about stell bridge?Let's talk about it.Look back and forward at steel bridge construction.

The original Steel Bridge opened in 1901.

For 60 years, three toots from a passing boat alerted the bridge tender to open the structure.

Using a big “watch key” crank, the tender could be seen huffing and puffing as he walked in a circle. It took 27 turns in low gear, or seven in high gear, to open the draw. But that wasn’t the toughest chore for bridge tenders. Theodore Brickhouse told The Pilot in 1961 that on winter nights, tenders hung 16 kerosene lanterns to mark the bridge.

A ship slammed into an approach in the 1930s, cutting it in half. The bridge was closed for weeks while workers rebuilt it. In 1960, Hurricane Donna sent a half-sunken barge into the bridge’s underpinnings, causing about $4,000 worth of damage.

Further complicating matters, heavily loaded trucks were not heeding the warning signs and were crossing the narrow steel structure. C.C. Battige, assistant bridge engineer for the Highway Department, told The Pilot he was worried one of those trucks might crash through the old bridge decking.

Those worries were allayed when in February 1961, the drawbridge was closed. The horse-and-buggy holdover, one of the last hand-operated structures in Virginia, was to be demolished and replaced by an electric-powered, push-button-operated bascule-type bridge.

The new Steel Bridge opened in April 1962.

And more than 50 years later, crews are hard at work to replace it yet again.

Though it’s far less work to open, those openings still prompt huffing and puffing – this time from motorists stuck in traffic.

Dominion Boulevard is one of the region’s most notorious bottlenecks because four lanes of traffic merge into two to cross the bridge. About 32,500 vehicles travel across it daily, the city said.

There are openings on the hour seven days a week from 6 a.m. to 6 p.m. and on demand from 6 p.m. to 6 a.m., with restrictions for morning and evening rush-hour traffic.

As the city’s population boomed in the 1990s, widening Dominion Boulevard became a priority.

“By 2040, the demographers are predicting that over 318,000 people will call Chesapeake home,” Mayor Alan Krasnoff said during a groundbreaking ceremony last December. “Fifty years ago, I doubt anyone could imagine that kind of transformational growth, but grow we have … and grow we will.”

The 3.8-mile project is designed to ease traffic by widening to four lanes the Steel Bridge and Dominion Boulevard, between Cedar Road and Great Bridge Boulevard. The drawbridge will be replaced with a tolled, fixed span.

While improving traffic on land, it also will free boaters from the headache of one more stop on the Intracoastal Waterway.

On its website, the city of Chesapeake also said the fixed span is more economical because there is less upkeep and operational cost than with a movable bridge. It also was designed to accommodate anticipated traffic in 2034.

The $345 million project should be completed in 2017.

20th floor,Tower B ,Taiyi Shangcheng,Zhonghua Street,Hengshui City,Hebei Province,China.
Tel: +86-318-8538202
Mob:+86-18678456530
Fax: +86-318-2210707
MSN: ztwqqq1985@hotmail.com
Skype: dachengdc678
Email:dcrubber1996@126.com
jen_dacheng@126.com
ztwqqq1985@hotmail.com
Contact:Jenny Lee

Dominion Blvd. closed near Steel Bridge into Friday

Dominion Boulevard will be closed in both directions near the Steel Bridge into Friday morning.

The closure, which began about 2 p.m., is scheduled to continue until 6 a.m., a city news release said. Drivers can use the Va. 168 Bypass or George Washington Highway as alternate routes.

The closure is not related to any incidents or injuries at the bridge. Work crews are widening Dominion Boulevard.

While placing concrete for a new bridge pier, crews noticed the concrete was not properly stabilized, the release said. Because of how close the pier is to the road, the contractor wanted to close the road as a safety precaution until a full inspection could be completed.