3 ms·
In the old days, the New York subway systems were mostly built by cut and cover, where they more or less dig up the street, build the tunnels and stations,throw
by Zach_the_Lizard 4y ago
In the old days, the New York subway systems were mostly built by cut and cover, where they more or less dig up the street, build the tunnels and stations,throw dirt back on top, and pave the road again.
Is that always possible? No. But when it is, it's almost certainly going to be much cheaper and faster.
For bonus points, throw all the ancient utility lines in conduit so the next infrastructure project isn't a disaster.
Nowadays we get the DC Metro, where a mostly above ground extension in a highway median was delayed for years because....I'm not sure exactly.
- Glide 4y agoThe DC metro is ridiculous. I'm cynical enough to think that the only way the Silver Line would have been done faster would have been to shutdown DCA so politicians would be forced to use Dulles. Even then they would probably just have drivers. IIRC, there are issues with the concrete used on the new platforms too.
- clairity 4y agothey're doing cut and cover on some fraction (maybe 1/3) of the purple line subway extension here in LA. it's still a bloated, expensive, late mess of a project, so technique matters little relative to incentive structure on total cost.