Rumor has it that alegendary six-headed monster lurks in the deep waters of the Tyrrhenian Seabetween
2010,the world'slongest bridge will weigh nearly 300,000 tons一equivalent to the iceberg that sank the Titanic一and stretch 5 kilometers long."That's nearly 50 percent
longer than anyother bridge ever built."says structural engineer Shane Rixon.
_______(47)They'resuspension bridges,massive structures built to span vast water channels orgorges.A suspension bridge needs just two towers to shoulder the structure's
mammoth weight,thanks to hefty supporting cables slung between the towers and anchored firmlyin deep pools of cement at each end of the bridge.The
Bridge will have two54,100-ton towers,which will support most of the bridge's load.The beefy cablesof the bridge,each 2 meter in diameter, will hold up the longest and
widest bridge deckever built.
When constructionbegins on the Messina Strait Bridge in 2005,the first job will be to erect two370 meter-tall steel towers._______(48)Getting these cables up will be
something. It's notjust their length一totally5.3 kilometers一but their weight._______(49)
After loweringvertical"suspender"cables from the main cables,builders will erect a60- meter一wide 54,630一ton steel roadway,or deck一wide enough toaccommodate 12
lanes of traffic.Thedeck's weight will pull down on the cables with a force of 70,500 tons.Inreturn,the cables yank up against their firmly rooted anchors with a force of
139,000 tons一equivalent to the weight of about100,000 cars. Those anchors are essential._______(50)
A.Someenvironmentalists are against the project on biological grounds.
B.What do theworld's longest bridges have in common?
C. If true ,one dayyou might spy the beast while zipping(呼啸而过)across the Messina Strait Bridge.
D.They're what willkeep the bridge from going anywhere.
E.The second jobwill be to pull two sets of steel cables across the strait,each set being abundle of 44,352 individual steel wires.
[单选题]The World's LongestBridgeRumor has it that alegendaiy six-headed monster lu
[单选题]The World's LongestBridgeRumor has it that alegendaiy six-headed monster lu
[单选题]The World's LongestBridgeRumor has it that alegendaiy six-headed monster lu
[单选题]The World's LongestBridgeRumor has it that alegendaiy six-headed monster lu
[单选题]The World's LongestBridgeRumor has it that alegendary six-headed monster lu
[单选题]The World's LongestBridgeRumor has it that alegendaiy six-headed monster lu
[单选题]The World's LongestBridgeRumor has it that alegendary six-headed monster lu
[单选题]The World's LongestBridgeRumor has it that alegendary six-headed monster lu
[单选题]The World's LongestBridgeRumor has it that alegendary six-headed monster lu
[单选题]The World's LongestBridgeRumor has it that alegendary six-headed monster lu