How did the two tunnels that made the channel tunnel meet?

Anyone like to explain how the two tunnels going from england and the other from france, met up under the english channel. I was watching the show that is on discovery today, and they never really explain how they got the two tunnels to meet up so exactly.

Anyone like to explain, as i have always wondered about this and no one seems to be able to explain it.

Any explanations, on how they dug two tunnels under the sea, and both met up?

Its amazing what you can do with a data collector and a total station isnt it. Its called Surveying man. Its my livelyhood. Simple trig functions work wonders dont they.

MessOnTheFED!

Originally posted by andy1033
Anyone like to explain how the two tunnels going from england and the other from france, met up under the english channel. I was watching the show that is on discovery today, and they never really explain how they got the two tunnels to meet up so exactly.

Anyone like to explain, as i have always wondered about this and no one seems to be able to explain it.

Any explanations, on how they dug two tunnels under the sea, and both met up?

Do not know much about science and stuff but would a gps and a height meter not make ends meet? I am convinced that some scientist here on ATS can explain into depths where to start and where to end.

reply to post by MessOnTheFED!


You telling it was that simple. I have always wondered how they got it to meet, but your saying it was just simple surveying.

It will prob be a lot of methods.

My money is on a lot of serious laser work... You already know the points where you started digging either side and then you have very very very! accurate surveyors constantly stopping work and doing maths.

Originally posted by MessOnTheFED!
Its amazing what you can do with a data collector and a total station isnt it. Its called Surveying man. Its my livelyhood. Simple trig functions work wonders dont they.

MessOnTheFED!

LOL!!!! You know, 10,000 years from now, scientists and archaeologists will be baffled at this feat. AND the conspiracy theorists will shout from the mountain tops that the tunnel was built by ancient aliens. Mankind could never be that clever.

Could the lasers penetrate the rocks, and meet under the sea? Is that what your saying they did?

I will give you 3 options. Try to mark the correct answer:

1) Magic
2) They just crossed their fingers and hoped for the best
3) Math

[edit on 5-1-2010 by henriquefd]

reply to post by andy1033


That is exactly what im telling you. Surveyors put a boaring machine on line and tell them the depth to go and eventualy the two meet up with great accuracy if your dealing with some good surveyors and engineers.

MessOnTheFED!

reply to post by andy1033


No man. Think about it like your going at it blind and the other side is doing the same. Then you meet in the middle. Within millimeters.

MessOnTheFED!

reply to post by MessOnTheFED!


Yep but did they use a laser and the laser went through the rock, to the other side, and met up. Can lasers go though 40kms of rock and meet up at other end?

For those saying it was simple math, do you know how much could of gone wrong, in just using maths, to meet the two tunnels?

reply to post by Aggie Man


Lol you are right. Im going to let you in on a little secret. Do you have any idea who invented surveying??? Ancient Egyptians.

MessOnTheFED!

reply to post by andy1033


NO!


You dig from a given spot - they dig from a given spot.

You both want to meet - on paper, simple! - In practice you have to constantly know your exact position in 3 dimensions!

So you always work from all your previous 'known' positions in the old xyz! - the first being the place where the first shovel hit the earth.

You've seen surveyors with their theodolites out and about before right? - Well normally line of sight is fine - for ultra accurate then lasers and computers come in to play.



Laser seeing through rocks? Did you go to school at any point? - edit: Are you trying to get ATS to do your homework for you

[edit on 5/1/2010 by Now_Then]

reply to post by andy1033


No they didnt use lasers. The lasers used in surveying need a prism at the other end. Some of the newer robots can shoot distances without a prism though. But thats 70,000 duckets there. They deffinately do not go through rock. They can barely go through tree canopy.

reply to post by Aggie Man


lol, thats why i think man before our present civilizations made the pyramids, its just that we do not know that history. But your right, maybe one day they will look back on the channel tunnel, and ponder lol.

reply to post by Now_Then


And remember.... Level Rod on the celing in a cave...

MessOnTheFED!

reply to post by MessOnTheFED!


Thats what i wanted to know. If it was just down to math and surveying, or did they use some sort of laser or something to guide them, that was going through all the rock or something to both ends.

Its amazing, but they never do explain really how they got them two tunnels to meet with such accuracy.

reply to post by andy1033


Andy... Ancient Egyptians invented surveying. I realy hate to bust your bubble.

MessOnTheFED!

Originally posted by andy1033
For those saying it was simple math, do you know how much could of gone wrong, in just using maths, to meet the two tunnels?

The simple thing about maths is that (usually) if your right then you are right - no matter how you look at the sum, no matter who looks at the sum - backwards and forwards it's either right or wrong.

So yes - simple maths - dedicated engineers and some serious kit.



You do realise you may as well ask how did any of the tube stations in London get dug - or any other tunnel?

reply to post by andy1033


Degrees Minutes and Seconds. Vertcal Angles and Distance is all you need.

MessOnTheFED!