Caltrans External Exit Tabs & 240 Inch Tall Overhead Signs

Started by jeffe, April 18, 2021, 03:48:13 AM

Previous topic - Next topic

CentralCAroadgeek

Coming back from the dead here (I always lurk but haven't posted anything here since 2015) to report that a reconstruction project on US-101 in Carpinteria has added some new BGSes with external exit tabs



There's several more signs like this along that stretch of road, so it looks like something that will be sticking around in California now


Max Rockatansky


CentralCAroadgeek


Max Rockatansky

Quote from: CentralCAroadgeek on January 04, 2022, 06:16:00 PM
Quote from: Max Rockatansky on January 04, 2022, 06:08:23 PM
I'm assuming that whole gantry is brand new also?

Judging by pre-2017 Street View footage (https://www.google.com/maps/@34.399645,-119.5141685,3a,90y,127.18h,90.18t/data=!3m7!1e1!3m5!1soDgwN8pSSfrkVq4OQAMLhg!2e0!5s20150401T000000!7i13312!8i6656), this is the very first gantry at this exit! It used to be a sign on the ground before this one

Got it, that makes sense then.  Apparently Caltrans (maybe someone can expound on this) used internal exit tabs on existing gantries so it doesn't alter the wind load capacity.  A new gantry would be designed with a wind load factoring then external tab into the design.

Scott5114

Wow. If I didn't know better, I'd have no clue those were Caltrans signs. They look...normal.
uncontrollable freak sardine salad chef

vdeane

Quote from: CentralCAroadgeek on January 04, 2022, 05:52:12 PM
Coming back from the dead here (I always lurk but haven't posted anything here since 2015) to report that a reconstruction project on US-101 in Carpinteria has added some new BGSes with external exit tabs



There's several more signs like this along that stretch of road, so it looks like something that will be sticking around in California now
I can't see the picture.
Please note: All comments here represent my own personal opinion and do not reflect the official position of NYSDOT or its affiliates.

Techknow

Can't see the photo either. Looks like it might be linked to a private Google Photo?

I'm glad there's more of this, but it seems to vary greatly on Caltrans district to district. I reported in the CA catch-all thread that the I-580 Exit 12 supplementary guide sign has yet to be replaced (still has graffiti). This weekend my family and I went shopping at Livermore and I also noticed there were 3 more brown BGSes with internal exit tabs on I-580. So maybe District 4 hasn't caught on yet.

Scott5114

I happened to have showed the photo to someone else over Messenger, so I was able to rehost it.
uncontrollable freak sardine salad chef

deathtopumpkins

Disclaimer: All posts represent my personal opinions and not those of my employer.

Clinched Highways | Counties Visited

SeriesE

Quote from: Scott5114 on January 04, 2022, 11:44:55 PM
I happened to have showed the photo to someone else over Messenger, so I was able to rehost it.


The main sign being shorter than the gantry height looks sloppy

roadfro

Quote from: SeriesE on January 06, 2022, 04:16:54 PM
Quote from: Scott5114 on January 04, 2022, 11:44:55 PM
I happened to have showed the photo to someone else over Messenger, so I was able to rehost it.


The main sign being shorter than the gantry height looks sloppy

Given Caltrans' past inclination for undersized signs and less-than-ideal sign layouts, I can more than forgive these sign panels not being as tall as the truss... These are gold standard in comparison to much of their past work.

This might actually be related to Caltrans' wind loading standards...
Roadfro - AARoads Pacific Southwest moderator since 2010, Nevada roadgeek since 1983.

jeffe

Quote from: roadfro on January 06, 2022, 10:39:49 PM

This might actually be related to Caltrans' wind loading standards...

Yeah, this sign truss is of the previous design (note there are no gusset plates) before the versatile truss was introduced and it doesn't meet the current wind loading standards.

Some projects were designed with external tabs before the versatile truss was available.  They all use this reduced panel design to meet wind loading standards.

Given the long lead time to design these projects, it will probably be a while until we see a project constructed that was initiated after the current sign and truss standards were introduced.

For example, the plans to widen US-101 between Novato and Petaluma use the versatile truss, but the sign panels still have internal tabs.

SeriesE

There's another external tab sign at CA-57 S signed for Lincoln Avenue.

Scott5114

Quote from: SeriesE on January 06, 2022, 04:16:54 PM
The main sign being shorter than the gantry height looks sloppy

Sign gantry height is supposed to have no bearing on the size of a sign panel. If it does, the sign is incorrectly laid out. According to MUTCD, sign panel size is dictated by the legend+margins and nothing else.
uncontrollable freak sardine salad chef

SeriesE

Quote from: Scott5114 on January 18, 2022, 02:43:44 PM
Quote from: SeriesE on January 06, 2022, 04:16:54 PM
The main sign being shorter than the gantry height looks sloppy

Sign gantry height is supposed to have no bearing on the size of a sign panel. If it does, the sign is incorrectly laid out. According to MUTCD, sign panel size is dictated by the legend+margins and nothing else.

California's convention is to have the sign equal or taller than the gantry height, so that's why I felt it looked off when the sign is shorter than the gantry.

Scott5114

Quote from: SeriesE on January 18, 2022, 03:46:13 PM
Quote from: Scott5114 on January 18, 2022, 02:43:44 PM
Quote from: SeriesE on January 06, 2022, 04:16:54 PM
The main sign being shorter than the gantry height looks sloppy

Sign gantry height is supposed to have no bearing on the size of a sign panel. If it does, the sign is incorrectly laid out. According to MUTCD, sign panel size is dictated by the legend+margins and nothing else.

California's convention is to have the sign equal or taller than the gantry height, so that's why I felt it looked off when the sign is shorter than the gantry.

California's convention is against the MUTCD.
uncontrollable freak sardine salad chef

stevashe

Quote from: Scott5114 on January 18, 2022, 03:49:32 PM
Quote from: SeriesE on January 18, 2022, 03:46:13 PM
Quote from: Scott5114 on January 18, 2022, 02:43:44 PM
Quote from: SeriesE on January 06, 2022, 04:16:54 PM
The main sign being shorter than the gantry height looks sloppy

Sign gantry height is supposed to have no bearing on the size of a sign panel. If it does, the sign is incorrectly laid out. According to MUTCD, sign panel size is dictated by the legend+margins and nothing else.

California's convention is to have the sign equal or taller than the gantry height, so that's why I felt it looked off when the sign is shorter than the gantry.

California's convention is against the MUTCD.

Are you sure? The MUTCD certainly prescribes minimum standards for sign dimensions, but I'm fairly certain there's no rule prohibiting exceeding them. And California is certainly not the only state to use taller signs than necessary for aesthetic reasons.

Alps

Quote from: stevashe on January 18, 2022, 04:09:08 PM
Quote from: Scott5114 on January 18, 2022, 03:49:32 PM
Quote from: SeriesE on January 18, 2022, 03:46:13 PM
Quote from: Scott5114 on January 18, 2022, 02:43:44 PM
Quote from: SeriesE on January 06, 2022, 04:16:54 PM
The main sign being shorter than the gantry height looks sloppy

Sign gantry height is supposed to have no bearing on the size of a sign panel. If it does, the sign is incorrectly laid out. According to MUTCD, sign panel size is dictated by the legend+margins and nothing else.

California's convention is to have the sign equal or taller than the gantry height, so that's why I felt it looked off when the sign is shorter than the gantry.

California's convention is against the MUTCD.

Are you sure? The MUTCD certainly prescribes minimum standards for sign dimensions, but I'm fairly certain there's no rule prohibiting exceeding them. And California is certainly not the only state to use taller signs than necessary for aesthetic reasons.
There are definitely other agencies (I wanna say Ohio has adopted this now) that will make all signs on the same gantry the same height.

roadfro



Quote from: Alps on January 18, 2022, 07:20:47 PM
Quote from: stevashe on January 18, 2022, 04:09:08 PM
Quote from: Scott5114 on January 18, 2022, 03:49:32 PM
Quote from: SeriesE on January 18, 2022, 03:46:13 PM
Quote from: Scott5114 on January 18, 2022, 02:43:44 PM
Quote from: SeriesE on January 06, 2022, 04:16:54 PM
The main sign being shorter than the gantry height looks sloppy

Sign gantry height is supposed to have no bearing on the size of a sign panel. If it does, the sign is incorrectly laid out. According to MUTCD, sign panel size is dictated by the legend+margins and nothing else.

California's convention is to have the sign equal or taller than the gantry height, so that's why I felt it looked off when the sign is shorter than the gantry.

California's convention is against the MUTCD.

Are you sure? The MUTCD certainly prescribes minimum standards for sign dimensions, but I'm fairly certain there's no rule prohibiting exceeding them. And California is certainly not the only state to use taller signs than necessary for aesthetic reasons.
There are definitely other agencies (I wanna say Ohio has adopted this now) that will make all signs on the same gantry the same height.

I feel like much of California's past convention on older signage has been that the sign height dictates the truss depth of the sign bridge... With every sign on the structure is the same height. But then if any sign on the gantry needs a change of legend later, it has to fit within the confines of the original sign.

I think this is starting to change with new sign and structure standards... But it's gonna take a long time to see a lot of significant changes in the field.


Count Nevada as one of those agencies where all signs on a gantry are typically the same height. There's a few one-off exceptions, but that's typically the rule...
Roadfro - AARoads Pacific Southwest moderator since 2010, Nevada roadgeek since 1983.

Scott5114

Quote from: stevashe on January 18, 2022, 04:09:08 PM
Are you sure? The MUTCD certainly prescribes minimum standards for sign dimensions, but I'm fairly certain there's no rule prohibiting exceeding them. And California is certainly not the only state to use taller signs than necessary for aesthetic reasons.

Quote from: 2009 MUTCD §2E.14
Standard:
04 For all freeway and expressway signs that do not have a standardized design, the message dimensions shall be determined first, and the outside sign dimensions secondarily.

So deciding "all of our signs are going to be 90" tall" (or whatever) before the message dimensions have been determined is against the MUTCD. Deciding "all of the signs on this gantry are going to be the same height" before the message dimensions have been determined is against the MUTCD.

Now if you make the all of the signs equal to the maximum sign height, yeah, it's better than if you make them all too small and cram too much message onto one panel. But either way, it's equally wrong according to the rules, and making the signs too big is wasteful of materials and looks dumb.
uncontrollable freak sardine salad chef

ran4sh

Quote from: Scott5114 on January 19, 2022, 02:46:49 AM

So deciding "all of our signs are going to be 90" tall" (or whatever) before the message dimensions have been determined is against the MUTCD.

I agree, California does this and it's wrong.

Quote from: Scott5114 on January 19, 2022, 02:46:49 AMDeciding "all of the signs on this gantry are going to be the same height" before the message dimensions have been determined is against the MUTCD.

Now if you make the all of the signs equal to the maximum sign height, yeah, it's better than if you make them all too small and cram too much message onto one panel. But either way, it's equally wrong according to the rules, and making the signs too big is wasteful of materials and looks dumb.

Disagree. It's the same thing as states that use larger-than-standard signs in other cases, such as Wisconsin's arrows for route markers. FHWA has never really cared if a state exceeds the sign standards.

Case in point Georgia, Illinois, Texas, Michigan, etc all have provisions for BGS to be larger than necessary while still complying with minimum sign message and spacing standards. If the FHWA wanted signs to be the exact size for a standard then they would have cracked down on some of these states, but they clearly don't care.
Control cities CAN be off the route! Control cities make NO sense if signs end before the city is reached!

Travel Mapping - Most Traveled: I-40, 20, 10, 5, 95 - Longest Clinched: I-20, 85, 24, 16, NJ Tpk mainline
Champions - UGA FB '21 '22 - Atlanta Braves '95 '21 - Atlanta MLS '18

Alps

Quote from: ran4sh on January 19, 2022, 01:12:54 PM
Quote from: Scott5114 on January 19, 2022, 02:46:49 AM

So deciding "all of our signs are going to be 90" tall" (or whatever) before the message dimensions have been determined is against the MUTCD.

I agree, California does this and it's wrong.

Quote from: Scott5114 on January 19, 2022, 02:46:49 AMDeciding "all of the signs on this gantry are going to be the same height" before the message dimensions have been determined is against the MUTCD.

Now if you make the all of the signs equal to the maximum sign height, yeah, it's better than if you make them all too small and cram too much message onto one panel. But either way, it's equally wrong according to the rules, and making the signs too big is wasteful of materials and looks dumb.

Disagree. It's the same thing as states that use larger-than-standard signs in other cases, such as Wisconsin's arrows for route markers. FHWA has never really cared if a state exceeds the sign standards.

Case in point Georgia, Illinois, Texas, Michigan, etc all have provisions for BGS to be larger than necessary while still complying with minimum sign message and spacing standards. If the FHWA wanted signs to be the exact size for a standard then they would have cracked down on some of these states, but they clearly don't care.
They haven't even cracked down on states taking decades to convert to mile-based exit numbers. They don't care in general.

J N Winkler

It's worth noting that the MUTCD language in § 2E.14 does not actually mandate the use of uniform criteria for space padding, so Caltrans can claim it is complying on the basis that it is choosing truss depth (and thus the height of all signs on the structure) according to the height of the tallest legend block on the signs.

Plus, as has been noted, other state DOTs have their own ways of fudging the criteria.  For example, we're all used to three-quarters capital letter height for interline space padding, but Minnesota DOT allows this to vary from half to full capital letter height.
"It is necessary to spend a hundred lire now to save a thousand lire later."--Piero Puricelli, explaining the need for a first-class road system to Benito Mussolini

stevashe

Quote from: Scott5114 on January 19, 2022, 02:46:49 AM
Quote from: stevashe on January 18, 2022, 04:09:08 PM
Are you sure? The MUTCD certainly prescribes minimum standards for sign dimensions, but I'm fairly certain there's no rule prohibiting exceeding them. And California is certainly not the only state to use taller signs than necessary for aesthetic reasons.

Quote from: 2009 MUTCD §2E.14
Standard:
04 For all freeway and expressway signs that do not have a standardized design, the message dimensions shall be determined first, and the outside sign dimensions secondarily.

So deciding "all of our signs are going to be 90" tall" (or whatever) before the message dimensions have been determined is against the MUTCD. Deciding "all of the signs on this gantry are going to be the same height" before the message dimensions have been determined is against the MUTCD.

Now if you make the all of the signs equal to the maximum sign height, yeah, it's better than if you make them all too small and cram too much message onto one panel. But either way, it's equally wrong according to the rules, and making the signs too big is wasteful of materials and looks dumb.

The sentence you quoted only says that the message dimensions must be determined first, but I don't see how enlarging the height a sign after making sure there is enough room for the message violates this standard. As I said before, this standard ensures that the minimum size of the sign must be enough to fit the message and any required margins, but does not prohibit increasing said margins.

And I disagree with you, I think a short sign next to a tall one can look a bit sloppy sometimes, though it depends on the proportions :P

Scott5114

Different sign sizes only look sloppy to me if they're vertically centered. If the bottoms of them are aligned, it looks much more orderly.
uncontrollable freak sardine salad chef



Opinions expressed here on belong solely to the poster and do not represent or reflect the opinions or beliefs of AARoads, its creators and/or associates.