Gantry Style/Design Between The States

[roadman]

Kentucky uses a unique style of side-mounted overhead, that I've heard some refer to as "erector set." I haven't seen this in any other state.

2017 Tennessee eclipse trip Day 2 - 039 by H.B. Elkins, on Flickr

2016 East End Bridge Trip Day 1 - 211 by H.B. Elkins, on Flickr

Multi-post cantilever upright.  Massachusetts allowed the use of a three post version of these in the 1960s and early to mid 1970s, particularly with aluminum structures.  The majority of these structures have since been replaced with single post upright/box truss horizontal cantilevers, but there are a few stragglers still in the field on the few sections of I-495 where signs haven't been recently updated.

Which brings up another sidebar question:  Are there any states that still allow the use of aluminum for sign structures/gantries?  Massachusetts discontinued the use of aluminum in 1974, except for projects that were in the construction phase.

[TheArkansasRoadgeek]

2017 Tennessee eclipse trip Day 2 - 039 by H.B. Elkins, on Flickr

Is that a "mumble" strip (Sinusidal Strip)? Not to be confused with its counterpart the rumble strip.

[hbelkins]

^^^

It's a sawed-in (as opposed to rolled-in) rumble strip.

[TheArkansasRoadgeek]

^^^

It's a sawed-in (as opposed to rolled-in) rumble strip.

Sounds laborious!

[epzik8]

I like my state's setup. It mostly has Clearview.

[jakeroot]

I like my state's setup. It mostly has Clearview.

[TheArkansasRoadgeek]

I like my state's setup. It mostly has Clearview.

Gross Clearview!

[roadman]

I like my state's setup. It mostly has Clearview.

Unfortunately, the font on the signs has little to do with the style of structure/gantry a particular state uses to hold those signs up.

[Mr_Northside]

Kentucky uses a unique style of side-mounted overhead, that I've heard some refer to as "erector set." I haven't seen this in any other state.

KY is the only place I've seen them.  I always thought KY had the most consistent design for their overheads  (granted, I've only personally been from Cincy to Louisville via I-71, and what I've seen in pictures on this site).  All of the "Side-Mounted" look like the ones posted, and the full overheads all have the same design, just changed for size/length requirements.

[lepidopteran]

For the record, the PA Turnpike/I-95 project seems to be making use of monotubes.

Not sure if they will be both on the pike and I-95 (or the soon-to-renamed I-295), though. 

Full link here: https://www.patpconstruction.com/paturnpikei95/current-sectiond10.aspx

[architect77]

North Carolina now uses pretty beefy pole/truss assemblies.
<iframe width="640" height="360" src="https://www.youtube.com/embed/nMkieZw_2JM" frameborder="0" allowfullscreen></iframe>

They also are increasing use of raised pedestal signs on shoulder without cantilever, I'm ambivalent for now on that.

Georgia uses a full sign bridge spanning across highway even for one small sign. It looks ridiculous, they're unwilling to go out and inspect bolts every couple of years for cantilevered signs (which I think are elegant ), therefore they don't do any cantilevers whatsoever anymore.

I-85 through Gwinnett has about 70 full sign bridges, maximizing visual clutter and ugliness for what was once a decent looking highway.

[hbelkins]

Kentucky uses a unique style of side-mounted overhead, that I've heard some refer to as "erector set." I haven't seen this in any other state.

KY is the only place I've seen them.  I always thought KY had the most consistent design for their overheads  (granted, I've only personally been from Cincy to Louisville via I-71, and what I've seen in pictures on this site).  All of the "Side-Mounted" look like the ones posted, and the full overheads all have the same design, just changed for size/length requirements.

Yes, Kentucky is consistent. The below is in Kentucky, but it's easy to tell that it's a Tennessee installation.



Because not too far away, well within the Volunteer State, you have this...

[J N Winkler]

Which brings up another sidebar question:  Are there any states that still allow the use of aluminum for sign structures/gantries?  Massachusetts discontinued the use of aluminum in 1974, except for projects that were in the construction phase.

Kansas DOT has allowed aluminum sign structures in recent contracts.  I think it may also have standard plan sheets for them, though I haven't checked recently.

[myosh_tino]

The dominant gantry style in California is the Pratt truss.  Unlike ones pictured earlier, California's trusses use a single pole (or poles for full-width gantries) to support the truss...

and some are painted...

California also uses monopoles (a.k.a. Tubular) which are almost always painted...

The final gantry style used in California is called the "Box-Beam".  It's basically a Pratt truss that's been wrapped in a metal sheeting.  While this is the most aesthetic, it was removed from Caltrans' Standard Plans in the early 2000's but many of them are still in use today.  These gantries are always painted and have been seen in mint green, dark green, reddish-brown and tan.

As a sidebar to this thread, which states have standard design plans for overhead sign supports/gantries, and which states allow the fabricators to choose the support/gantry design based on the span length/sign sizes/loading requirements/etc.?

Caltrans has standard design plans for all overhead gantries including mounting signs from overpasses.

[roadfro]

Nevada is similar to California.


The Pratt truss is the dominant style used throughout the state, and what you'll find in the NDOT's standard plans document.

There are a few Warren trusses used in older, light-duty sign applications (mostly on roads, but there is a pair of these on US 395 over Moana Lane in Reno)–I believe these are still seen in the standard plans, but I have not seen a new installation of this type in the last 15+ years.

NDOT used unpainted monotubes throughout the I-80 reconstruction in Reno-Sparks a few years ago. Monotubes are not in the standard plans AFAIK. I believe monotubes were used on this project because a unified design aesthetic was desired and the standard Pratt truss might not have been able to accommodate the APL signs at the US 395 interchange.

[myosh_tino]

There are a few Warren trusses used in older, light-duty sign applications (mostly on roads, but there is a pair of these on US 395 over Moana Lane in Reno)–I believe these are still seen in the standard plans, but I have not seen a new installation of this type in the last 15+ years.

These types of trusses are used in California too.  Caltrans calls them "lightweight" trusses.  Current standards state that only small warning signs (i.e. "Signal Ahead") or extinguishable message signs (i.e. "Meter On" or "Prepare to Stop") along with flashing beacons are allowed to be mounted on these trusses.  For example...

However, at one point Caltrans allowed small guide signs to be mounted on these trusses.  There are a few examples of that scattered throughout the state and here is one of them...

[Pink Jazz]

Arizona once used Pratt truss, but now uses monotubes.  Some older portions of the Phoenix area freeway system still have some of the truss gantries intact.

[TheArkansasRoadgeek]

Arizona once used Pratt truss, but now uses monotubes.  Some older portions of the Phoenix area freeway system still have some of the truss gantries intact.

I've always seen Arizona as a monotube state, same as California. I don't know.... Movies?

[Pink Jazz]

Arizona once used Pratt truss, but now uses monotubes.  Some older portions of the Phoenix area freeway system still have some of the truss gantries intact.

I've always seen Arizona as a monotube state, same as California. I don't know.... Movies?

There are still plenty of trusses on many of the older freeways in the Phoenix area. I don't recall seeing many trusses in the rural areas of the state though.  They are still very common on I-10 and SR 143 in the Phoenix area, with a small number still on I-17 and US 60; most of those surviving on the latter being full-widths (I think the one-sided ones were replaced by monotubes in a construction project in the early 2000s), although some one-sided trusses still survive east of Loop 202.

[ekt8750]

For the record, the PA Turnpike/I-95 project seems to be making use of monotubes.

Not sure if they will be both on the pike and I-95 (or the soon-to-renamed I-295), though. 

Full link here: https://www.patpconstruction.com/paturnpikei95/current-sectiond10.aspx

Both PennDOT and PTC have gone monotubes lately. All of their recent projects have used them.

Also good see that PTC has dumped Clearview.

[jeffandnicole]

For the record, the PA Turnpike/I-95 project seems to be making use of monotubes.

Not sure if they will be both on the pike and I-95 (or the soon-to-renamed I-295), though. 

Full link here: https://www.patpconstruction.com/paturnpikei95/current-sectiond10.aspx

Both PennDOT and PTC have gone monotubes lately. All of their recent projects have used them.

Also good see that PTC has dumped Clearview.

Everyone has dumped Clearview. Its not permitted anymore.

[Pink Jazz]

Everyone has dumped Clearview. Its not permitted anymore.

What about Texas?  Texas is the state that has been the most vocal on challenging the FHWA's decision, and several new Clearview signs have gone up well after the decision was announced.

[jakeroot]

AFAIK, Clearview is allowed on all signage that was approved before the date of revocation, not necessarily installed. Which is why new signs still pop up.

[TheArkansasRoadgeek]

For the record, the PA Turnpike/I-95 project seems to be making use of monotubes.

Not sure if they will be both on the pike and I-95 (or the soon-to-renamed I-295), though. 

Full link here: https://www.patpconstruction.com/paturnpikei95/current-sectiond10.aspx

Both PennDOT and PTC have gone monotubes lately. All of their recent projects have used them.

Also good see that PTC has dumped Clearview.

What's with the severe alignment with the sign to the right? They didn't even try to algin the top edges!

[jakeroot]

For the record, the PA Turnpike/I-95 project seems to be making use of monotubes.

https://www.patpconstruction.com/paturnpikei95/images/progress_photos/d1e_279.jpg

What's with the severe alignment with the sign to the right? They didn't even try to algin the top edges!

Sign on the left isn't finished yet. Will align properly soon enough.