2007-07-05 11:06:27 · 21 answers · asked by Anonymous in Science & Mathematics ➔ Engineering
So if I travel 120m under a bridge that carries a motorway above...is that a tunnel or a bridge? And joining landmass, does that include train platforms?
2007-07-05 11:19:07 · update #1
The effective word for tunnel is "through", rather than "under"
2007-07-06 05:05:54 · answer #1 · answered by zebedos 3 · 0⤊ 1⤋
A bridge is built to span a gorge, valley, road, railroad track, river, body of water, or any other physical obstacle. Designs of bridges vary depending on the function of the bridge and the nature of the terrain where the bridge is to be constructed.
A tunnel is an underground passage. The definition of what constitutes a tunnel is not universally agreed upon. However, in general tunnels are at least twice as long as they are wide. In addition, they should be completely enclosed on all sides, save for the openings at each end.
I hope this helps.
2007-07-05 11:11:59 · answer #2 · answered by Anonymous · 4⤊ 0⤋
bridges span some sort of land gap..whether it be a river, a gorge or whatever. A tunnel is a completely enclosed structure except for an entrance and an exit. The old covered bridges that you see in the northeast show a combination of a bridge and a tunnel.
2007-07-05 11:12:15 · answer #3 · answered by Victor L 1 · 0⤊ 1⤋
when the bridge ends against a cliff or hill side.
Good example, Golden gate bridge ends with the MacArthur tunnel on the north side of the expanse.
and the middle section of the Bay bridge (also in the San Fransisco bay area) passes through a man made hill on angel island.
2007-07-05 11:33:25 · answer #4 · answered by Stone K 6 · 0⤊ 0⤋
A bridge goes over the water. A tunnel is built to go through the water.
2007-07-05 11:17:06 · answer #5 · answered by Talaupa 5 · 0⤊ 1⤋
Interesting question. I think I would define the difference as the roof of a tunnel supports earth, while a bridge supports man-made things (e.g. buildings, cars, trains).
2007-07-06 00:00:10 · answer #6 · answered by Steve-Bob 4 · 1⤊ 0⤋
a bridge is a tunnel
if you got a road bridge going over a rail track then a train would go through a tunnel
2007-07-05 11:18:46 · answer #7 · answered by Melted Snowman 5 · 0⤊ 1⤋
A bridge goes over things - eg a road, river or train track.
A tunnel goes under things eg a mountain or a river
2007-07-05 11:16:22 · answer #8 · answered by scouserich 2 · 0⤊ 1⤋
A bridge spans something and a tunnel goes under something.
2007-07-05 11:09:48 · answer #9 · answered by McCanns are guilty 7 · 0⤊ 1⤋
When the road or whatever passing beneath is longer than it is wide
2007-07-05 19:02:12 · answer #10 · answered by Martin 5 · 1⤊ 0⤋