|
|
Post by Jason Saunders on Jun 29, 2010 19:51:23 GMT -8
For those interested, this 45 minute episode of Mega Engineering goes inside a massive tunnel boring machine and shows how it works. It's basically an underground moving factory. v.youku.com/v_show/id_XMTEyMzI3NDMy.html |
|
|
|
Post by skater on Dec 10, 2013 17:30:46 GMT -8
wouldnt it be cheaper if the long, straight portions of the subway tunnels were built as cut and cove instead? the shallower stations would not manly be cheaper to build but alp to operate because of shorter escalators, etc. seems to me there may be more impacts during construction, buy the money saved may be worth it. plus some of the savings could be used to compenste businesses affected. I wonder why cut and cover is never considered.
|
|
|
|
Post by bzcat on Dec 11, 2013 10:41:17 GMT -8
Generally speaking, cut and cover is only used in urban area if you need the vertical access during construction (e.g. building underground stations). TBM is cheaper and more effective (faster) if you are just building tunnels, especially straight ones.
|
|
|
|
Post by culvercitylocke on Dec 17, 2013 19:45:34 GMT -8
that reminds me, I've been meaning to ask, how far down Wilshire did tunneling originally go before being stopped? Is there a significant amount of extra tunnel already built?
|
|
|
|
Post by masonite on Dec 17, 2013 21:35:27 GMT -8
that reminds me, I've been meaning to ask, how far down Wilshire did tunneling originally go before being stopped? Is there a significant amount of extra tunnel already built? Not sure what you are talking about? In the 90s, there were plans to go from the current Western terminus to Pico and San Vicente in Mid City, but the MTA had to reorganize and it never went anywhere. Construction was never started. In the early 80s there were plans to take the subway along Wilshire into West LA, but this was before the subway ever existed anywhere in LA. |
|
|
|
Post by fissure on Dec 17, 2013 23:15:20 GMT -8
that reminds me, I've been meaning to ask, how far down Wilshire did tunneling originally go before being stopped? Is there a significant amount of extra tunnel already built? Have you never been to Wilshire/Western station? You can clearly see the concrete wall (not a knockout panel) just past the end of the platform. They may have to close the station when the TBM breaks through. |
|
|
|
Post by bzcat on Dec 18, 2013 11:16:45 GMT -8
They wouldn't use the TBM going east so no need to close the Western station  |
|
|
|
Post by culvercitylocke on Dec 18, 2013 12:40:56 GMT -8
I thought they had to stop drilling down wilshire because of some sort of gas problem in an office building? That's why waxman banned subway construction at the federal level.
|
|
|
|
Post by masonite on Dec 18, 2013 17:48:26 GMT -8
I thought they had to stop drilling down wilshire because of some sort of gas problem in an office building? That's why waxman banned subway construction at the federal level. There was an explosion in the basement of a Ross Dress for Less across from the Farmer's Market in 1985. Waxman went after the federal ban on fed funds being used for the subway in this section of town after this. Keep in mind the subway hadn't even started major construction even in Downtown at this point. |
|
|
|
Post by fissure on Dec 21, 2013 11:47:46 GMT -8
They wouldn't use the TBM going east so no need to close the Western station Huh? I thought the plan was to drop them in at La Brea and bore east to Western and west to La Cienega from there. I don't think the EIR even allows cut and cover for the non-station segments. |
|
