如题所述
世界第一拱桥是朝天门长江大桥，它以其巨大的跨度位居全球拱桥之首。朝天门长江大桥最初被称为王家沱长江大桥，后来更名为红岩衫返长江大桥，最终在2004年2月定名为朝天门长江大桥。 construction began in December 2004. On April 29, 2009, the bridge was officially opened to traffic. Spanning the Yangtze River, the bridge connects the Xinban District in the west with the Dadukou District in the east, and is 1,741 meters in total length with a main span of 552 meters. The bridge's upper deck features a six-lane, primary urban roadway with a design speed of 60 kilometers per hour, while the lower deck accommodates two lanes of double-track urban rail transit on each side, with two additional lanes reserved. The bridge was constructed using the BT (Build-Transfer) mode.
The design specifications of the bridge are as follows: The bridge has a double-deck layout. The upper deck truss accommodates a two-way six-lane urban main road with a width of 26 meters. There are 2.5-meter-wide sidewalks on both sides of the main truss, resulting in a total deck width of 36.5 meters. The lower deck features a double-track urban rail transit in the center, with a spacing of 4.2 meters between the lines and 7-meter-wide roadways on each side. The roadway on the deck is classified as a primary roadway with a design speed of 60 kilometers per hour. The lane configuration includes six lanes on the upper deck and two lanes on the lower deck. The minimum clearance height for the roadway is 5 meters; each lane is 3.75 meters wide; the sidewalks are 2 times 5 meters wide; the rail transit standard is for double-track rail transit with a spacing of 4.2 meters; the designed speed of travel is 80 to 100 kilometers per hour; the net width of the track gauge is not less than 9.2 meters, and the net height from the track to the top is not less than 6.5 meters; the design reference period is 100 years. The above information refers to the Chaotianmen Yangtze River Bridge entry on Baidu Encyclopedia.
The design specifications of the bridge are as follows: The bridge has a double-deck layout. The upper deck truss accommodates a two-way six-lane urban main road with a width of 26 meters. There are 2.5-meter-wide sidewalks on both sides of the main truss, resulting in a total deck width of 36.5 meters. The lower deck features a double-track urban rail transit in the center, with a spacing of 4.2 meters between the lines and 7-meter-wide roadways on each side. The roadway on the deck is classified as a primary roadway with a design speed of 60 kilometers per hour. The lane configuration includes six lanes on the upper deck and two lanes on the lower deck. The minimum clearance height for the roadway is 5 meters; each lane is 3.75 meters wide; the sidewalks are 2 times 5 meters wide; the rail transit standard is for double-track rail transit with a spacing of 4.2 meters; the designed speed of travel is 80 to 100 kilometers per hour; the net width of the track gauge is not less than 9.2 meters, and the net height from the track to the top is not less than 6.5 meters; the design reference period is 100 years. The above information refers to the Chaotianmen Yangtze River Bridge entry on Baidu Encyclopedia.
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