NOT a bridge. An inverse bridge? A tunnel.
ISTHA needs a 300 ft. long, two lane wide tunnel built under an existing six-lane road. Somebodies done this before. How is it done?
Could you horizontally drill, sliding a steel tube, say 18" in diameter, filling with rebar and concrete? Like a mini skyscraper foundation caisson. Dozens side-by-side. This would be the roof of the tunnel. Then excavate and support?
Quote from: dzlsabe on May 26, 2016, 12:18:05 AM
NOT a bridge. An inverse bridge? A tunnel.
ISTHA needs a 300 ft. tunnel built under an existing six-lane road. Somebodies done this before. How is it done?
Could you horizontally drill, sliding a steel tube, say 18" in diameter, filling with concrete, more steel? Like a mini skyscraper foundation caisson. Dozens side-by-side. Then excavate and support?
https://en.wikipedia.org/wiki/Big_Dig (https://en.wikipedia.org/wiki/Big_Dig)
Can they do cut and cover?
Not without completely disrupting multiple lanes of traffic on the 4th busiest tollroad in the nation.
Quote from: Stratuscaster on May 28, 2016, 10:30:15 PM
Not without completely disrupting multiple lanes of traffic on the 4th busiest tollroad in the nation.
Would luv to see the Edens Spur #s. The Tristate OK. The Spur is??... guessing about 50% SHORT of where it could/should be.
And NO...cut and cover would never work. But, ISTHA plans to completely rebuild "something" in five years.
They did it at the M1/A43 junction (https://www.google.co.uk/maps/@52.2082422,-0.9361675,3a,75y,211.1h,90.09t/data=!3m6!1e1!3m4!1sPf4IGJa7S6vY0taMxdJfrw!2e0!7i13312!8i6656). Pretty easy to do - just as you say - you force in a bridge deck and supports, extract underneath, strengthen. The M1 never closed (I believe there were some shoulder closures to deal with putting in the railings and stuff) as they built a new parallel carriageway for the A43.
Aren't subways built underground in this manner?. I don't think there's anything unusual about it whatsoever. The biggest issue is the existing infrastructure under the road, such as drainage, water, sewer, and electrical lines, all of which are a bigger issue to reroute.
And they don't necessarily need to keep the entire road open. They can shift traffic around as needed.
Quote from: Roadrunner75 on May 26, 2016, 12:51:56 AM
Quote from: dzlsabe on May 26, 2016, 12:18:05 AM
NOT a bridge. An inverse bridge? A tunnel.
ISTHA needs a 300 ft. tunnel built under an existing six-lane road. Somebodies done this before. How is it done?
Could you horizontally drill, sliding a steel tube, say 18" in diameter, filling with concrete, more steel? Like a mini skyscraper foundation caisson. Dozens side-by-side. Then excavate and support?
https://en.wikipedia.org/wiki/Big_Dig (https://en.wikipedia.org/wiki/Big_Dig)
That's what they did in Boston to get the freeway tunneled beneath a hugely active subway line. First they froze the unconsolidated earth underneath the tracks and then slowly shoved a caisson the size of the new highway underneath a few feet at a time, excavated the frozen, mostly clay soil and build the tunnel walls and ceiling.
Roadways are much easier to tunnel underneath though because you can shift the traffic around sharper curves within the right of way.
300 feet is more than enough room to shift 6 lanes around to build one half of a cut-and-cover tunnel at a time. 6 lanes at 12' each is 72 feet plus some buffer for temporary barriers and marginal shoulder. Worst case scenario, that's 100 feet across, so there's 50 foot of play on either side to deal with construction or site-specific constraints to build one half of a 300 foot tunnel at a time.
Heres the aerial...
https://www.google.com/maps/@42.1504536,-87.8723461,302m/data=!3m1!1e3
About three hundred ft. long and two lanes wide under the one 294 banner.
Quote from: dzlsabe on June 05, 2016, 06:17:43 PM
Heres the aerial...
https://www.google.com/maps/@42.1504536,-87.8723461,302m/data=!3m1!1e3
About three hundred ft. long and two lanes wide under the one 294 banner.
Looks like there is plenty of room to move roadways around temporarily for construction of what I assume are the missing system ramp connections?
Im talking about NOT moving ANY roadways. Drill, baby, drill.
Modern subways are usually dug with tunnel-boring machines, which can do some insanely delicate manuvers (Crossrail in London had a clearance of inches above/below existing Tube lines at one of the stations).
Did not the big dig do that. They dug the new I-93 beneath the elevated green elephant, using slur walls to support the elevated highway piers while digging around it. In fact at one point they dug over 100 feet deep, I read in Wikipedia, because of a subway line.
Under this...
https://www.google.com/maps/@42.1498769,-87.8736014,314m/data=!3m1!1e3
https://www.google.com/maps/@42.1506393,-87.8732989,3a,75y,270h,90t/data=!3m7!1e1!3m5!1sjTcPYaF5aMGZ9ytV-BTICw!2e0!6s%2F%2Fgeo0.ggpht.com%2Fcbk%3Fpanoid%3DjTcPYaF5aMGZ9ytV-BTICw%26output%3Dthumbnail%26cb_client%3Dmaps_sv.tactile.gps%26thumb%3D2%26w%3D203%26h%3D100%26yaw%3D102.42104%26pitch%3D0!7i13312!8i6656
https://www.google.com/maps/@42.1506393,-87.8732989,3a,75y,90t/data=!3m7!1e1!3m5!1sjTcPYaF5aMGZ9ytV-BTICw!2e0!6s%2F%2Fgeo0.ggpht.com%2Fcbk%3Fpanoid%3DjTcPYaF5aMGZ9ytV-BTICw%26output%3Dthumbnail%26cb_client%3Dmaps_sv.tactile.gps%26thumb%3D2%26w%3D203%26h%3D100%26yaw%3D102.42104%26pitch%3D0!7i13312!8i6656
Rotate clockwise.
Quote from: dzlsabe on May 26, 2016, 12:18:05 AM
NOT a bridge. An inverse bridge? A tunnel.
ISTHA needs a 300 ft. long, two lane wide tunnel built under an existing six-lane road. Somebodies done this before. How is it done?
CSX Transportation is (re) building The Virginia Avenue Tunnel (http://www.virginiaavenuetunnel.com/) that runs (in part) under I-695 (https://en.wikipedia.org/wiki/Interstate_695_(District_of_Columbia)) (Southeast Freeway) in the District of Columbia. Google Map of the area here (https://www.google.com/maps/dir/38.8812724,-77.0059027/38.876974,-76.9896984/@38.877952,-76.9982255,16z/data=!4m2!4m1!3e0) showing the two tunnel portals.
I spotted this plan on Skyscraperpage forums about a project to "freeway-lizing" a gap of Crowchild Trail in Calgary by tunneling it while the service roads will be on surface.
http://forum.skyscraperpage.com/showpost.php?p=7472970&postcount=5216
http://forum.skyscraperpage.com/showpost.php?p=7473000&postcount=5218
They need to do this with the I-5 SB to WA 520 ramp. Currently, it does go through a tunnel under the express lanes, but it is currently a left exit so there's a lot of weaving issues. They also need to do this with the 520 WB to I-5 SB offramp, except it's an overpass so it could be more easily rebuilt.
This is totally hypothetical, because there's not really much room to work with here without having to buy expensive property, but it really is a shame that it wasn't designed well to begin with. I guess that back in the early-60s nobody was really familiar with all the problems that left exits and entrances cause.
Dude, as you've been told numerous times before, there is no room for ramps there, tunnel or otherwise.
Quote from: dzlsabe on May 26, 2016, 12:18:05 AM
NOT a bridge. An inverse bridge? A tunnel.
ISTHA needs a 300 ft. long, two lane wide tunnel built under an existing six-lane road. Somebodies done this before. How is it done?
Could you horizontally drill, sliding a steel tube, say 18" in diameter, filling with concrete, more steel? Like a mini skyscraper foundation caisson. Dozens side-by-side. Then excavate and support?
Yes, you can. They've used that technique at least once in Atlanta, for these MARTA tunnels under I-285 (https://www.google.com/maps/@33.7699722,-84.2323415,269m/data=!3m1!1e3).
Quote from: dzlsabe on May 26, 2016, 12:18:05 AM
NOT a bridge. An inverse bridge? A tunnel.
ISTHA needs a 300 ft. long, two lane wide tunnel built under an existing six-lane road. Somebodies done this before. How is it done?
Could you horizontally drill, sliding a steel tube, say 18" in diameter, filling with concrete, more steel? Like a mini skyscraper foundation caisson. Dozens side-by-side. Then excavate and support?
This was done back in 2014 in Lynchburg, Virginia at Liberty University. There was a need to connect the campus with Wards Road, a major road to the west of campus. The problem was the Norfolk Southern tracks in between the two -- the former Southern Railway line between Atlanta and Washington, D.C. that carries a significant amount of freight traffic and the Amtrak Crescent. The solution was to tunnel under the tracks:
The tunneling method used for the project was the first of its kind in North America. It involved pulling two jacked concrete boxes, each standing 26 feet tall and weighing 4.2 million pounds, through the earth with six motors and more than 160 cables creating the four-lane tunnel (two lanes each way). It also marked the first time the Norfolk Southern Railway had allowed concrete boxes that large to be pulled under a live, active, main rail. (http://www.liberty.edu/news/index.cfm?PID=18495&MID=146025)
The design and construction was handled by Brierley Associates of East Syracuse, New York. (see http://www.brierleyassociates.com/twin-box-tunnels-liberty-university-lynchburg-virginia/)
See https://goo.gl/maps/BBLjmA4quPn for the location and street view.
Bruce in Blacksburg
Quote from: VTGoose on September 12, 2016, 10:58:11 AM
Quote from: dzlsabe on May 26, 2016, 12:18:05 AM
NOT a bridge. An inverse bridge? A tunnel.
ISTHA needs a 300 ft. long, two lane wide tunnel built under an existing six-lane road. Somebodies done this before. How is it done?
Could you horizontally drill, sliding a steel tube, say 18" in diameter, filling with concrete, more steel? Like a mini skyscraper foundation caisson. Dozens side-by-side. Then excavate and support?
This was done back in 2014 in Lynchburg, Virginia at Liberty University. There was a need to connect the campus with Wards Road, a major road to the west of campus. The problem was the Norfolk Southern tracks in between the two -- the former Southern Railway line between Atlanta and Washington, D.C. that carries a significant amount of freight traffic and the Amtrak Crescent. The solution was to tunnel under the tracks:
The tunneling method used for the project was the first of its kind in North America. It involved pulling two jacked concrete boxes, each standing 26 feet tall and weighing 4.2 million pounds, through the earth with six motors and more than 160 cables creating the four-lane tunnel (two lanes each way). It also marked the first time the Norfolk Southern Railway had allowed concrete boxes that large to be pulled under a live, active, main rail. (http://www.liberty.edu/news/index.cfm?PID=18495&MID=146025)
The design and construction was handled by Brierley Associates of East Syracuse, New York. (see http://www.brierleyassociates.com/twin-box-tunnels-liberty-university-lynchburg-virginia/)
See https://goo.gl/maps/BBLjmA4quPn for the location and street view.
Bruce in Blacksburg
Just one of THOSE, for 300 ft should do it. Thank you.
Springdale (AR) Country Club did this about 20 years ago. The drilled under the highway, but still had to close two lanes at a time to finish. Now you have a nice golf cart tunnel under 71B ;)
Quote from: triplemultiplex on June 05, 2016, 01:44:34 AM
That's what they did in Boston to get the freeway tunneled beneath a hugely active subway line. First they froze the unconsolidated earth underneath the tracks and then slowly shoved a caisson the size of the new highway underneath a few feet at a time, excavated the frozen, mostly clay soil and build the tunnel walls and ceiling.
Actually, this method was used to build the tunnel extending I-90 to the Williams Tunnel where it crosses underneath the heavy rail lines entering South Station, which is a multiple track approach where the highway goes underneath it. The I-93 tunnel, which goes above the Red Line subway and beneath the Blue Line subway, was constructed with the cut and cover method.
Thought slurry wall construction was used on I-93 as well.
Quote from: Rothman on September 23, 2016, 09:43:30 AM
Thought slurry wall construction was used on I-93 as well.
Yes, slurry walls were used on the I-93 tunnel, to avoid the potential for wood pilings supporting older adjacent buildings from drying out. However, the actual tunnel was dug using the cut and cover method, not by freezing the earth and drilling through it as was done for the I-90 tunnel under the South Station approaches.