Types of Big Green Sign mounting posts?

[ColossalBlocks]

What types of BGS mounts do they use in your states?

Missouri uses the standard open rafter like mount.

https://goo.gl/maps/FbrSXwd2LPS2

[plain]

Virginia uses various ones but they're all for the most part similar to your standard example.

I've always loved the ones on the Charleston (WV) expressways though. I-95 in Baltimore had similar ones but they're all gone except right at the tunnel. I wonder why MD felt the need to replace those?

[Pink Jazz]

Arizona used to use truss gantries but now uses tubular gantries.  However, many truss gantries still remain in place.

[jeffandnicole]

These 2 examples pretty much sums up what NJDOT uses.

https://goo.gl/maps/MaHTndgPTc52

https://goo.gl/maps/KogZCwfHYAw

[jakeroot]

WashDOT uses this cheap box-type monotube for all installations (full and partial width), and has been using this gantry style for over 25 years.

They're typically unpainted, but painted gantries are becoming more common. Those are often brown or green; this strange peach/tan color was used along I-705 back in the late 80s (last photo).







British Columbia's MOTI uses traditional monotubes (though much more rigid in appearance). Partial-width raised gantry signs are very rare. Most overhead signage is APL (which requires full-width gantries).

[index]

From what I've seen, NCDOT only uses truss gantries, and does not have a standard gantry, (correct me if i'm wrong) like FDOT and some other DOTs do. I've seen a variety of different looking truss gantries.

[roadman]

MassDOT only provides general specifications (such as wind design speed) for BGS overhead structure design, and leaves the exact support design up to the fabricator, subject to review and approval of the calculations and drawings by either MassDOT or the project designer.  The only exception to this policy was for the Big Dig project, where monotube supports were specified for purely aesthetic reasons (remember that Big Dig = $21 billion beautification project with a highway component).  In that case, very specific design requirements were provided to the fabricator for the supports, with the result that the sign panels had to be specifically designed not to exceed the maximum loading of the supports (i.e. total opposite of standard BGS and gantry design practice).

As a result, sign support structures on Massachusetts highways are a combination of single chord supports, trichords, and box truss structures.  The most common cantilever design these days is a box truss member on a single post upright.  Monotubes are generally not used for cost reasons, and are also considered impractical for longer spans due to the camber requirements and lack of redundancy (unlike trichords or box trusses) if they get struck.

[kphoger]

I believe Kansas' overheads are called box truss gantries, but I might have my terminology wrong.

[roadman]

I believe Kansas' overheads are called box truss gantries, but I might have my terminology wrong.

You have it right.  In the sign support world, "box truss" normally refers to a four-chord open truss structure, which are the type of sign structures I've seen in most photos and GSV views of Kansas highways I've viewed.  Some agencies also use the term to describe an enclosed fabricated rectangular support - like the sign supports used on Boston's original elevated Central Artery.

[briantroutman]

Does anyone know what these are?
https://goo.gl/maps/SULkBo19Kew

Perhaps I'm misremembering, but I think they used to be a little more common across Pennsylvania, but the one linked above is the only one I've noticed in recent years.

[kphoger]

Does anyone know what these are?
https://goo.gl/maps/SULkBo19Kew

Perhaps I'm misremembering, but I think they used to be a little more common across Pennsylvania, but the one linked above is the only one I've noticed in recent years.

That looks like a box truss gantry, similar to Kansas.

[ET21]

Illinois uses mainly truss gantries:


But inter-mixed in Chicagoland you have brown beams:

[Scott5114]

It should be noted that there are multiple types of truss:


Missouri uses a Pratt truss. Illinois uses either a Warren or a Vierendeel. Minnesota uses a modified Warren.

The Kansas "box truss" (also in use in Arkansas, New York, and others) uses two modified Warrens, one of which is flipped 180° from the other, and connected by 45° braces:

[cpzilliacus]

Virginia uses various ones but they're all for the most part similar to your standard example.

I've always loved the ones on the Charleston (WV) expressways though. I-95 in Baltimore had similar ones but they're all gone except right at the tunnel. I wonder why MD felt the need to replace those?

Because all of I-95 in Baltimore City is maintained by the Maryland Transportation Authority (MdTA), which is very aggressive when it comes to replacing  signs.  Those structures can also be found on I-83 in Baltimore City.

[kphoger]

It should be noted that there are multiple types of truss:


Missouri uses a Pratt truss. Illinois uses either a Warren or a Vierendeel. Minnesota uses a modified Warren.

The Kansas "box truss" (also in use in Arkansas, New York, and others) uses two modified Warrens, one of which is flipped 180° from the other, and connected by 45° braces:

Thank you very much for that explanation.  That's practically sticky-worthy.

[roadman]

Does anyone know what these are?
https://goo.gl/maps/SULkBo19Kew

Perhaps I’m misremembering, but I think they used to be a little more common across Pennsylvania, but the one linked above is the only one I’ve noticed in recent years.

That looks like a box truss gantry, similar to Kansas.

Correct.  It is a box truss gantry with modified tri-chord uprights.  Very unusual design that I've only seen in Pennsylvania.  They may also be aluminum structures, which would explain the unusual uprights.

[ColossalBlocks]

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

[ColossalBlocks]

WashDOT uses this cheap box-type monotube for all installations (full and partial width), and has been using this gantry style for over 25 years.

They're typically unpainted, but painted gantries are becoming more common. Those are often brown or green; this strange peach/tan color was used along I-705 back in the late 80s (last photo).







British Columbia's MOTI uses traditional monotubes (though much more rigid in appearance). Partial-width raised gantry signs are very rare. Most overhead signage is APL (which requires full-width gantries).

I really like the box monotube design. Especially when painted.

[TheHighwayMan3561]

Minnesota used to use the Pratt truss; you can still see a few around the Twin Cities area.

[JoePCool14]

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.

[Thunderbyrd316]

   While watching a first season episode of CHiPs (1977) a little while ago I noticed at least 2 monotube style gantries. (Both painted a tan-beige color.) I did not realise that CalTrans was using those so long ago. The first time I ever remember actually seeing that style of gantry anywhere was in the mid '80's on the Blackstone Freeway in Fresno. ("Painted" that sort of "rust/brown" color/texture.)

As a side note, there are a VERY few of this style of gantry in Washington state. (Painted grey.) I really like this style of gantry and wish Oregon used it. I find it much preferable either to Washington's "box tube" gantry or Oregon's (I'm not really sure what you would call it but it ain't attractive) style.

[ET21]

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.

Those seem to be placed randomly. I don't know if their for public input or a trend of what's to come. Some of those are gonna get demolished when the Central Tri-State gets rebuilt

[JoePCool14]

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.

Those seem to be placed randomly. I don't know if their for public input or a trend of what's to come. Some of those are gonna get demolished when the Central Tri-State gets rebuilt

ISTHA was probably trying to be a WisDOT wannabe, but they aren't nearly as good. WisDOT ones actually have a design and are colored differently. ISTHA's are boring cylinders. I'm not sure what their intent was, but it honestly seems kinda pointless at the moment.

[myosh_tino]

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.

[Pink Jazz]

For some other states, New Mexico uses monotubes.  Nevada I think uses Pratt truss.  Texas however seems to vary by district, with the El Paso district using monotubes as standard but other districts using truss.