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Monotube Gantries

Started by thenetwork, May 23, 2020, 09:50:50 AM

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thenetwork

Hard to believe that montube gantries have been around for at least 45 years (saw my first ones on the TV show CHiPs).  Even harder to believe that it took so long for their design to be used regularly across the country.

What states have adopted/changed to the use of monotube gantries for their overhead signs?  Also, for the individual state, is it a sporadic placement, widespread, or is it a vanity design for a specific highway?

COLORADO:  Slowly becoming the norm state-wide as new installs and replacements of older gantries.

NEW MEXICO:  In-use Statewide.

OHIO: Sporadic, though really becoming the norm in the Toledo area.

UTAH: Seems to be the norm, and has been for quite a number of years, save for some exceptions (Legacy Parkway in SLC).

Others?


US 89

#1
Quote from: thenetwork on May 23, 2020, 09:50:50 AM
UTAH: Seems to be the norm, and has been for quite a number of years, save for some exceptions (Legacy Parkway in SLC).

Every overhead gantry on Legacy is still monotube:



And yes, they have been the norm since at least the mid-1980s (if not earlier). The I-80/I-215/Foothill interchange used to be full of original truss gantries, but those were all replaced a few summers ago. As far as I know, there are only five truss gantries still standing in the entire state - three at the I-15/I-70 interchange, and two at the SR 56 interchange in Cedar City.

STLmapboy

I don't believe MO has any monotube gantries. I-15 in San Diego does have some distinctive peach-colored ones, but those are the only ones I know of in Socal.
Teenage STL area roadgeek.
Missouri>>>>>Illinois

Scott5114

OK seems to be installing them only in urban counties. There was a bridge project on I-35 where it crosses from Cleveland to McClain County. All of the gantries on the Cleveland side were monotubes, but the one on the McClain County side was a traditional truss.
uncontrollable freak sardine salad chef

Brandon

Chicago has, along the Chicago Skyway mostly.  Otherwise, ISTHA has a triangular gantry they use, and IDOT has a square gantry they use (both before and after the brown gantries of the 1980s and 1990s).
"If you think this has a happy ending, you haven't been paying attention." - Ramsay Bolton

"Symbolic of his struggle against reality." - Reg

-- US 175 --

Some newer installs along NTTA toll roads (Bush Turnpike and Dallas N. Tollway especially) have monotubes, but they haven't completely replaced traditional gantries or roadside BGSes.

Great Lakes Roads

#6
None on the INDOT or the Toll Road, but three local streets uses it near Interstate 465: Keystone Parkway SB @96th Street in Carmel, 86th Street, and 71st Street.

The Tampa Region in Florida uses monotubes on I-275, I-4, and FL SR 60.

The I-80 corridor through Reno has monotubes gantries throughout the area (only place in Nevada to use monotubes gantries).


wriddle082

In general, most southeastern states don't use them, with the exception of FL.  I have seen exactly 0 in the Carolinas, GA, AL, LA, and MS.  In TN, I have only seen them on the ring road serving Nashville International Airport.  I cannot remember whether or not they exist in KY now because I want to say I saw some along the Ohio River Bridges project sites in the Louisville area.

bing101

California some sections uses Monotube gantries.

ilpt4u

Quote from: Brandon on May 24, 2020, 12:14:39 AM
Chicago has, along the Chicago Skyway mostly.  Otherwise, ISTHA has a triangular gantry they use, and IDOT has a square gantry they use (both before and after the brown gantries of the 1980s and 1990s).
ISTHA uses monotube gantries for the I-Pass ORT Toll Booth lanes. Also ISTHA has used monotube gantries at newer ramp plazas as well

hobsini2

Quote from: Brandon on May 24, 2020, 12:14:39 AM
Chicago has, along the Chicago Skyway mostly.  Otherwise, ISTHA has a triangular gantry they use, and IDOT has a square gantry they use (both before and after the brown gantries of the 1980s and 1990s).
I never liked those ugly brown gantries. I'm glad Illinois is going back to the trusses. Now if only the stoplights on lesser roads where you don't need 3 signals on an arm would go back to the truss.
I knew it. I'm surrounded by assholes. Keep firing, assholes! - Dark Helmet (Spaceballs)

hobsini2

Quote from: ilpt4u on May 24, 2020, 02:04:35 PM
Quote from: Brandon on May 24, 2020, 12:14:39 AM
Chicago has, along the Chicago Skyway mostly.  Otherwise, ISTHA has a triangular gantry they use, and IDOT has a square gantry they use (both before and after the brown gantries of the 1980s and 1990s).
ISTHA uses monotube gantries for the I-Pass ORT Toll Booth lanes. Also ISTHA has used monotube gantries at newer ramp plazas as well
For the toll plazas, yes. and it makes sense for the to use them for the I-Pass lanes. But ISTHA never uses them for the green sign gantries. They had the opportunity to switch to it recently with the widening of I-90 and the extension of the Elgin O'Hare 390 Tollway but didn't. BTW, the plazas on the Elgin O'Hare 390 Tollway are not the same style as the I-Pass lanes on say 294 or 355. Those are more rounded. These are more squared. https://www.google.com/maps/@41.9868679,-88.1300475,3a,75y,38.68h,95.25t/data=!3m6!1e1!3m4!1sqTrAUdZD1ngrKP7cdP1VMA!2e0!7i16384!8i8192?hl=en or this https://www.google.com/maps/@41.9844772,-88.0070691,3a,75y,262.62h,89.67t/data=!3m6!1e1!3m4!1ssZqBQg5kHfNuQS9G_UNlXw!2e0!7i16384!8i8192?hl=en

One thing ISTHA has changed recently is the Plaza signs. They used to be green like this at Boughton Rd Plaza 89 for the non I-Pass lanes. https://www.google.com/maps/@41.7332056,-88.0352473,3a,75y,163.41h,89.51t/data=!3m6!1e1!3m4!1sCFNgOLAdVFwANzH4eg_goA!2e0!7i16384!8i8192?hl=en
They are blue now at that plaza as of a feww weeks ago. Unfortunately, I do not have a pic of it yet.
I knew it. I'm surrounded by assholes. Keep firing, assholes! - Dark Helmet (Spaceballs)

Roadwarriors79

For Arizona, monotube gantries are used almost everywhere. The South Mountain section of Loop 202 is the only new stretch of freeway that does NOT use the monotube style.

ErmineNotyours

Quote from: hobsini2 on May 24, 2020, 03:58:35 PM
Quote from: ilpt4u on May 24, 2020, 02:04:35 PM
Quote from: Brandon on May 24, 2020, 12:14:39 AM
Chicago has, along the Chicago Skyway mostly.  Otherwise, ISTHA has a triangular gantry they use, and IDOT has a square gantry they use (both before and after the brown gantries of the 1980s and 1990s).
ISTHA uses monotube gantries for the I-Pass ORT Toll Booth lanes. Also ISTHA has used monotube gantries at newer ramp plazas as well
For the toll plazas, yes. and it makes sense for the to use them for the I-Pass lanes. But ISTHA never uses them for the green sign gantries. They had the opportunity to switch to it recently with the widening of I-90 and the extension of the Elgin O'Hare 390 Tollway but didn't. BTW, the plazas on the Elgin O'Hare 390 Tollway are not the same style as the I-Pass lanes on say 294 or 355. Those are more rounded. These are more squared. https://www.google.com/maps/@41.9868679,-88.1300475,3a,75y,38.68h,95.25t/data=!3m6!1e1!3m4!1sqTrAUdZD1ngrKP7cdP1VMA!2e0!7i16384!8i8192?hl=en or this https://www.google.com/maps/@41.9844772,-88.0070691,3a,75y,262.62h,89.67t/data=!3m6!1e1!3m4!1ssZqBQg5kHfNuQS9G_UNlXw!2e0!7i16384!8i8192?hl=en

One thing ISTHA has changed recently is the Plaza signs. They used to be green like this at Boughton Rd Plaza 89 for the non I-Pass lanes. https://www.google.com/maps/@41.7332056,-88.0352473,3a,75y,163.41h,89.51t/data=!3m6!1e1!3m4!1sCFNgOLAdVFwANzH4eg_goA!2e0!7i16384!8i8192?hl=en
They are blue now at that plaza as of a feww weeks ago. Unfortunately, I do not have a pic of it yet.

Strange that PA uses monotubes for toll plazas, because the last latticework gantry I saw in Washington was for the photo toll equipment near Evergreen Point Bridge here.  This turned out to be a very temporary installation and they moved the equipment at bit to the west on to the same square monotubes the state has put up since the 80s.

When I was commuting to a job in 1994 I noticed something odd in the construction of a monotube sign.  Where the horizontal and vertical tube met was connected with a cast aluminum bracket.  Nothing odd about that, but when the installation was complete, they covered it with a sleeve that made it look like the tubes were welded together directly.  Or maybe I'm imagining things, but I swear I saw that bracket and I now can't see any indications that the tubes aren't welded together.

tdindy88

Quote from: wriddle082 on May 24, 2020, 08:27:50 AM
In general, most southeastern states don't use them, with the exception of FL.  I have seen exactly 0 in the Carolinas, GA, AL, LA, and MS.  In TN, I have only seen them on the ring road serving Nashville International Airport.  I cannot remember whether or not they exist in KY now because I want to say I saw some along the Ohio River Bridges project sites in the Louisville area.


I'm pretty sure the Ohio River Bridges projects did not feature any monotube gantries. I don't think I've ever seen any kind of signage like that in Kentucky at all, or Indiana for that matter.

bing101


Here is the first known case of a monotube gantry in California at the CA-118 freeway.



MarkF

The first monotubes I saw in CA were when the I-15 Escondido bypass opened in 1977, the streetlights had a similar design:


jakeroot

#18
^^^^
Quote from: MarkF on May 25, 2020, 04:04:16 AM
The first monotubes I saw in CA were when the I-15 Escondido bypass opened in 1977, the streetlights had a similar design:
https://i.imgur.com/A7b8bQQ.jpg

Those almost appear to be rounded version of the welded box monotubes that WSDOT uses prolifically. Unless I'm seeing the image incorrectly.

jakeroot

#19
WSDOT uses their welded box monotube standard that doesn't seem to have a domestic equivalent (at least not full width). They are very similar to the gantries used in some European countries like Germany, France, Austria, Norway, or Sweden, although only in appearance. How WSDOT constructs their gantries, I really don't know. They must weld them on the spot or something.

There have been traditional monotubes installed in Washington State, but none for a good twenty years or so; examples here and here (and all along the WA-14 Freeway in general). All examples I'm familiar with are in Clark County, just across the river from Oregon.

So, to add to the list:

WASHINGTON STATE: curved monotube gantries used sparingly in southwest part of state; box monotube structures are current standard for all overhead gantries.

Here's a picture of Washington's current highway gantries...obviously not a traditional monotube design, but does it count for the purpose of this thread?


ErmineNotyours


EpicRoadways

The only ones in MN were installed in 2008 along the I-35W St. Anthony Falls Bridge in Minneapolis. AFAIK they haven't been used since.

https://goo.gl/maps/JnHKdvZSTEesMn3f9

jakeroot

Quote from: ErmineNotyours on May 25, 2020, 11:30:42 PM
Also a curved monotube near Wenatchee.  https://goo.gl/maps/YgdBkDwKyLm1D4g66

Sweet find! I had no idea there were any curved monotubes outside of Clark County. Although this is rather strange with the double monotube setup. This has to have been a one-off assembly.

deathtopumpkins

Massachusetts used monotubes throughout the Big Dig project area, but hasn't put up a new one since, switching back to more traditional trusses.

Example: https://goo.gl/maps/jqu6EkNq1Srdp93D6

MassDOT did use single or double mast arms for overhead signs for a while, e.g.: https://goo.gl/maps/DnDB7jQhGH34Ax6o9 though it seems new installations usually use traditional trusses.
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Clinched Highways | Counties Visited

jp the roadgeek

CTDOT seemed to use the curved monotube gantries from around 2000 to about 2010-2015.  They are quite prominent on I-95, including the Q-Bridge project.  However lately, they seem to have switched to a mixture of single chorded trusses (mostly to replace bridge mounted signage) and squared off tube gantries.  It looks like the full chorded truss May be making a comeback, as I see several newish ones in a storage area that look like they're reserved for the CT 72 sign replacement/exit renumbering.
Interstates I've clinched: 97, 290 (MA), 291 (CT), 291 (MA), 293, 295 (DE-NJ-PA), 295 (RI-MA), 384, 391, 395 (CT-MA), 395 (MD), 495 (DE), 610 (LA), 684, 691, 695 (MD), 695 (NY), 795 (MD)



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