Types of Big Green Sign mounting posts?

[tribar]

Illinois uses mainly truss gantries:


But inter-mixed in Chicagoland you have brown beams:

Around St Louis the brown beams make quite the appearance. https://goo.gl/maps/T7p2HZjBJ5v

IDOT generally uses the brown gantries (Not a fan personally of them), while ISTHA uses standard truss. However, they've been using box gantries with concrete pillars more recently, as seen here.

IDOT doesn't seem to use the brown gantries anymore and have replaced several of them with the fully braced design.  I kind of liked them, as they were something different. They seem to blend in well in the city but not so much in the suburbs (where they're rarely used anyway)

The ISTHA box gantries with the concrete supports definitely have an awkward look to them and just seem outdo place.

[tribar]

Illinois uses mainly truss gantries:


But inter-mixed in Chicagoland you have brown beams:

You forgot the Chicago Skyway, which uses a mono tube design.

[AMLNet49]

There are 3 common types of overhead sign structures in use by Caltrans...

1. Truss (more specifically a Pratt truss)


This is, by far, the most common gantry seen in California.


2. Box Beam


While still pretty common on freeways in the San Francisco Bay Area, the Box Beam gantry was removed from Caltrans' standard plans in the early 2000's but many remain in the field.


3. Monotubes


Monotubes are IMO, the least common of the 3 types of gantries seen in California but as the Box Beams are phased out, this style of gantry and the Pratt truss will be the only overhead sign structures left in Caltrans' standard plans.

In my opinion the more interesting part of California's overhead signage is the gantries that are not full-span. They use several designs that are cool looking and are not used in any other state as far as I know. It would be interesting to get an explanation of some of the advantages and disadvantages of these designs, and why no other states use them.

Here are some examples:
(This first one may be used in Nevada as well)

[roadman]

The box truss on single pole upright cantilever support is a common design in many states (including Massachusetts).  The only difference with the examples of California's design shown in the photos is that the box truss matches the panel width, and the upright diameter is smaller than more recent installations in other states.  From the mid-1970s until the mid-2000s, it was commonplace in many states to specify a maximum diameter (usually 18 inches) for overhead sign support uprights.  This requirement, which was for purely aesthetic reasons, became impractical for fabricators to meet with the adoption of the 2005 AASHTO Standard Specifications, and has been generally dropped since then.

[AMLNet49]

The box truss on single pole upright cantilever support is a common design in many states (including Massachusetts).  The only difference with the examples of California's design shown in the photos is that the box truss matches the panel width, and the upright diameter is smaller than more recent installations in other states.  From the mid-1970s until the mid-2000s, it was commonplace in many states to specify a maximum diameter (usually 18 inches) for overhead sign support uprights.  This requirement, which was for purely aesthetic reasons, became impractical for fabricators to meet with the adoption of the 2005 AASHTO Standard Specifications, and has been generally dropped since then.

Thank you, this also explains why uprights have seemed to be thicker in newer installations around the country.

[BelpheniaProject]

In Mississippi, they use the Modified Warren truss gantries.

[shadyjay]

In CT, new installations are either:  4-chord cantilever (side), 4-chord truss (full span), or monotube bridge (full span, as seen in the pic in the BC example on Pg1).  Tubular arch (side and full span) were used on new installations until quite recently.  Still lots of "angled supports" of various color schemes (grey, yellow, green, fluorescent green) around, and some older trusses and cantilevers.  From the early 1980s through the 2000s, the angled support was most common on new installations.

[peperodriguez2710]

I think in Spain we're a bit different. We use very different gantries (I've never seen box trusses, for example,  except for supporting cameras, radars or electronic signage aswell of the panels), and usually, they're shorter in comparison with the BGS they hold.
The most common gantry type for new installs used to be Vierendeels, like we see in my local beltway, and were the most popular choice for many, many years. You can still see loads of them across the country:


Some of them even date back to the 50s-60s as we see in this ancient gantry as Series E was only used in Spanish National roads (and this gantry use to be part of the N-III before it was relocated, that's the reason of the covered shields) back in that times:


They sometimes still use them in new installs, but now they're always light-weight versions, like this one:


Here's a variation they do in Andalusian autonomical roads, with the logo of the Junta de Andalucía:


Now, in new installs they use Pratt gantries (quite rarely though), and seldomly they done that with older ones. Also light weight sometimes:


Or this simple yet boring box ones, which have become extremely popular on new signs, I believe because of their cheapness. The most common ones are also light weight:



Then you have the stranger ones; seldomly used for new installs now (except a few models), like this Vierendeels-Pratt hybrids, which I've only seen in my island, and not uncommon in new installs, here's a pair:



You can also find, very rarely though, tubular Vierendeels all across the country, which usually are quite old:


This ones used to be extremely common on my local beltway, though they've been all replaced and I have only seen a pair in the mainland:


Then, I've only seen these in Andalusia, Vierendeels-Howe hybrids, quite new even:


And finally, the ancient square-tubular ones, which are very very very rarely seen:

[The High Plains Traveler]

Colorado's standard is now the single monotube. New Mexico uses a monotube with a horizontal support across the base of the signs. I'm also interested iin ground mount sign supports. Many states use I-beam posts that are self-supporting, but Nevada uses round signpost that uses back posts for wind resistance

[myosh_tino]

California uses wood posts for ground-mounted signs.

[Brandon]

Illinois uses mainly truss gantries:

Actually, these triangular ones are unique to the Illinois State Toll Highway Authority (ISTHA).  IDOT does not use them anywhere in the state.

But inter-mixed in Chicagoland you have brown beams:

IDOT District 1 was a big user of these in the in 1980s and 1990s.  They've also appeared in smaller numbers in District 5 (along I-39 and I-55 in Bloomington-Normal) and District 8 (along I-255).

IDOT usually uses these supports: https://goo.gl/maps/9T5ZAnPXMA22

[Brandon]

Michigan tends to use very squared-off supports: https://goo.gl/maps/zJLPbfTnqUw
And MDOT also uses these: https://goo.gl/maps/6U7ovdXGPWx

Wisconsin has a few different styles:
https://goo.gl/maps/1ogNTNdiXfS2
https://goo.gl/maps/FK2A9yFAffS2
https://goo.gl/maps/oEdMwKLKEWP2

Indiana uses these: https://goo.gl/maps/Sgv93Wb3WAR2

[Marc]

For the three state's I've lived in, I like Florida's the best. They use a triangular truss style gantry for sign bridges and cantilevered applications. Florida is one of the most consistent states I've been to in terms of gantry designs. I like that.

Sign bridge:


Cantilever:


What I always found interesting is how FDOT mounts signs on the non-flat side of the triangle for sign bridges that cross both sides of the roadway:


There are also a great deal of tubular arches in the Tampa area. Reminds me of being in a Rocky Mountain state:



My least favorite of the states I've lived in is Texas (by far). There is a lot of inconsistency due to the heavy use of aesthetic concrete in place of traditional steel poles. When they aren't using aesthetic concrete for the poles, TxDOT uses I-beams tethered together to make a truss design.

TxDOT standard sign bridge:


TxDOT standard cantilever:


TxDOT aesthetic design (one of hundreds of designs across the state–this is one of the least gaudy ones):

[Pink Jazz]

Texas actually seems to vary by district.  The El Paso District I know uses monotubes.

[Marc]

Texas actually seems to vary by district.  The El Paso District I know uses monotubes.

Yes, that is a newer trend I've noticed, especially in the districts that border New Mexico. Though, I've also seen a handful of monotubes in the Houston, Dallas, and Austin districts. I wish all of TxDOT would switch to monotubes exclusively.

[MattHanson939]

Colorado's standard is now the single monotube. New Mexico uses a monotube with a horizontal support across the base of the signs. I'm also interested iin ground mount sign supports. Many states use I-beam posts that are self-supporting, but Nevada uses round signpost that uses back posts for wind resistance

The standard in New Mexico is also the single monotube.  The only instances where you'll see the monotube with the horizontal support are along I-25 and I-40 in Albuquerque near the Big-I.  Other than that, just the single monotube is used.

[SkyPesos]

The full-length gantry mounting posts for the following 4 states are similar in many ways, yet also different from each other.
Illinois: Slightly angled vertical beams, 3 diagonal beams with none straight across.
Indiana: Straight up vertical beams (a bit thicker compared to the other 3 states), 3 diagonal beams with 3 beams straight across.
Ohio: Straight up vertical beams, 4 diagonal beams with none straight across.
Kentucky: Slightly angled vertical beams, 3 diagonal beams with 3 beams straight across.

[Scott5114]

Newer thread at https://www.aaroads.com/forum/index.php?topic=21307.0 –please use that one.