How to build a bridge!

[hon30critter]

I’m not sure how many of you have seen this but its definetely worth a look. Actually, the concept is pretty simple. You just have to build a machine big enough to do it.

https://www.youtube.com/embed/B6X82g2UZOs

Dave

[carl425]

So I guess this confirms the practice of doing the scenery before putting the girders and track in place.

[Steven_S]

That’s pretty interesting.

When they built the Millau Viaduct in France, they built the road deck on solid ground and then pushed it out over the valley. Here’s a 3D animation…

Skip ahead to 3:26.

Steve S

[gmpullman]

Accurate, precision engineering… nah, who needs it?

A 300 million dollar bridge in Cleveland, Ohio has one of it’s piers set almost THREE FEET out of alignment!

http://www.cleveland.com/metro/index.ssf/2012/07/pier_for_the_new_inner_belt_br.html

We’re talking modern day construction methods with GPS and laser guidance! 2’ 9" off! And all the contractors can do is scratch their heads?

Geez, the Hoosac Tunnel was dug (25,081 feet) in four segments back in 1875 and when the faces met the alignment was within 9/16^th of an inch! There’s many other examples of early engineering feats that were accomplished with amazing accuracy as well.

Thanks for posting these interesting videos, Dave & Steve.

Good day All, Ed

[hon30critter]

Steve:

Thanks for sharing the Millau bridge videos. Amazing!

Dave

[IRONROOSTER]

Accurate, precision engineering… nah, who needs it?

A 300 million dollar bridge in Cleveland, Ohio has one of it’s piers set almost THREE FEET out of alignment!

http://www.cleveland.com/metro/index.ssf/2012/07/pier_for_the_new_inner_belt_br.html

We’re talking modern day construction methods with GPS and laser guidance! 2’ 9" off! And all the contractors can do is scratch their heads?

Geez, the Hoosac Tunnel was dug (25,081 feet) in four segments back in 1875 and when the faces met the alignment was within 9/16^th of an inch! There’s many other examples of early engineering feats that were accomplished with amazing accuracy as well.

Thanks for posting these interesting videos, Dave & Steve.

Good day All, Ed

I like the part where they say it’s close enough.[:-^]

2 feet here 3 feet there pretty soon it all falls down.[#oops]

Paul

[Graffen]

It’s like the specifications for the Piper J3 Cub, a friend told me that the tolerances are +/- 1/2 an inch!!!

That makes swapping parts very interesting…

[BATMAN]

We’re talking modern day construction methods with GPS and laser guidance! 2’ 9" off! And all the contractors can do is scratch their heads?

That’s what happens when the worlds GPS system is used. While it would be spitting out the numbers in metric, someone at the construction company would insist that everything should be converted to feet and inches. Happens all the time.[:S]

[gmpullman]

While it would be spitting out the numbers in metric, someone at the construction company would insist that everything should be converted to feet and inches.

Gee, why does that sound familiar???

MARS CLIMATE ORBITER TEAM FINDS LIKELY CAUSE OF LOSS

A failure to recognize and correct an error in a transfer of information between the Mars Climate Orbiter spacecraft team in Colorado and the mission navigation team in California led to the loss of the spacecraft last week, preliminary findings by NASA’s Jet Propulsion Laboratory internal peer review indicate.

The peer review preliminary findings indicate that one team used English units (e.g., inches, feet and pounds) while the other used metric units for a key spacecraft operation. This information was critical to the maneuvers required to place the spacecraft in the proper Mars orbit.

C’est la vie…

Ed