Exit numbers on tabs in California

[pctech]

I noticed in some recent photographs of Texas highways that TXDOT seems to switching from above the sign exit# tabs to signs with the exit number in the sign. There is a divider line in the top part of the BGS. (like GADOT uses)

Mark

[Brandon]

I noticed in some recent photographs of Texas highways that TXDOT seems to switching from above the sign exit# tabs to signs with the exit number in the sign. There is a divider line in the top part of the BGS. (like GADOT uses)

Mark

Like GADOT?  Or like IDOT?  I haven't seen the pictures, but one (GA) centered the text while the other (IL) aligns the text to the side the exit is on.

[pctech]

TXDOT appears to using # aligned to the side that the exit is located on. You are right about GADOT, they center the number in the sign. I wonder what prompted the TX switch?

[Brandon]

TXDOT appears to using # aligned to the side that the exit is located on. You are right about GADOT, they center the number in the sign. I wonder what prompted the TX switch?

Wonder if TXDOT picked up an engineer from IDOT. 

[Big John]

You are right about GADOT, they center the number in the sign.

Since GDOT switched to the E(M) font, they also switched to the right-aligned exit tab which is not full width.

http://goo.gl/maps/uO2oX

[pctech]

I think that the way the exit# is displayed on this sign is a good compromise between an external #tab and the "in the box" ones .
https://www.aaroads.com/california/images099/ca-099_nb_exit_185_06.jpg

Mark

[vdeane]

It's better than the box things but it still wastes quite a bit of space.  If they used a tab there, they wouldn't have to cram the remaining info in such a tiny area.

[NJRoadfan]

I never understood why brand new gantries in California still have the lame "tab inside the sign". Being an all new structure, it shouldn't have any issues with wind load since it should have been engineered into the design. Around here when NJDOT wants to add a missing exit number that should have been posted 25 years ago, they just tack it on, usually removing dead florescent lighting in the process.

[myosh_tino]

I never understood why brand new gantries in California still have the lame "tab inside the sign". Being an all new structure, it shouldn't have any issues with wind load since it should have been engineered into the design. Around here when NJDOT wants to add a missing exit number that should have been posted 25 years ago, they just tack it on, usually removing dead florescent lighting in the process.

According to Caltrans employee and AARoads Forum member jrouse, all new sign trusses can accommodate external exit number tabs but there's a problem.

From the California Observations thread...

The Caltrans sign truss standards were significantly revised in early 2005.  At that time, it was noted that the new structures could accommodate exit number tabs.  However, to this day, there has not been a detail made available for mounting tabs.  I have spoken with the engineer who is responsible for the sign structure standard plans, and he has told me that he knows there is a need for such a detail, but it is not a high priority.

Apparently, since Caltrans got approval from the FHWA to implement internal exit number tabs, there's no rush to develop a method of attaching external tabs to overhead signs.  Besides, it's still cheaper to reuse existing sign trusses rather than buying new trusses.

It's better than the box things but it still wastes quite a bit of space.  If they used a tab there, they wouldn't have to cram the remaining info in such a tiny area.

This sign...



...would probably look like this if exit numbering wasn't required...



IMO, that's not "crammed in a tiny area" in my book.  To me, that looks like a standard pre-exit number exit direction sign.

[pctech]

What's interesting to me is a lack of a consistency by Caltrans. If you follow the AA roads photo sequence for CA-99 some of the BGS's have this type, some have the "in the box" type and some BGS's have no exit numbers. (i assume they are old ones that haven't been replaced yet). And I thought that LADODT was nutty! 

[vdeane]

According to Caltrans employee and AARoads Forum member jrouse, all new sign trusses can accommodate external exit number tabs but there's a problem.

From the California Observations thread...

The Caltrans sign truss standards were significantly revised in early 2005.  At that time, it was noted that the new structures could accommodate exit number tabs.  However, to this day, there has not been a detail made available for mounting tabs.  I have spoken with the engineer who is responsible for the sign structure standard plans, and he has told me that he knows there is a need for such a detail, but it is not a high priority.

Apparently, since Caltrans got approval from the FHWA to implement internal exit number tabs, there's no rush to develop a method of attaching external tabs to overhead signs.  Besides, it's still cheaper to reuse existing sign trusses rather than buying new trusses.

Why don't they just steal a method from another state?  Why re-invent the wheel?  Plus even the older structures can accommodate the tab (the exact same ones are used in other states with tabs); CA just has oddball wind loading standards.  If I was the FHWA, I would have said "No you don't get to use internal tabs, that wind load excuse is pure BS, now go actually read the MUTCD instead of just half-heartedly adding exit numbers to say you're adopting the MUTCD".

IMO, that's not "crammed in a tiny area" in my book.  To me, that looks like a standard pre-exit number exit direction sign.

That's probably because you live in CA.  I'm not comparing to pre-exit number; I'm comparing to other states (NYSDOT region 4 in particular).

[Brandon]

From the California Observations thread...

The Caltrans sign truss standards were significantly revised in early 2005.  At that time, it was noted that the new structures could accommodate exit number tabs.  However, to this day, there has not been a detail made available for mounting tabs.  I have spoken with the engineer who is responsible for the sign structure standard plans, and he has told me that he knows there is a need for such a detail, but it is not a high priority.

Apparently, since Caltrans got approval from the FHWA to implement internal exit number tabs, there's no rush to develop a method of attaching external tabs to overhead signs.  Besides, it's still cheaper to reuse existing sign trusses rather than buying new trusses.

And yet ISTHA can add exit number on aligned tabs west of Aurora on I-88 without replacing the trusses and without previously having instructions/documentation on installing such tabs.  Why can ISTHA do what CalTrans (both agencies that did not use exit numbering for years) cannot? 

[AndyMax25]

Hi Everyone,

I know this thread has been dormant for a while but I drove by this sign yesterday and actually went back to take a photo.

Anyone seen an offset exit tab like this?  The sign is quite wide, but other than possible tree obstruction I can't think of a logical reason for it being designed and put up this way. Thoughts??

This is SR-23 southbound at Ave de Los Arboles in Thousand Oaks.

[jeffe]

Thoughts??

This is SR-23 southbound at Ave de Los Arboles in Thousand Oaks.

There's an ongoing pavement rehabilitation project (07-302504) that will replace the overhead signs on this section of SR-23.  This sign in particular will be replaced with a sign that has the exit tab properly aligned all the way to the right.

If you look at the project plans for 07-302504, Sheet S-21, it shows the old sign with the oddly positioned exit tab.  I'm thinking they used field  observations to properly show the layout of the old sign; it would be really odd if it was designed that way and is mostly likely a fabrication error.

Based on Google Streetview it looks like the existing sign structure was installed shortly after February 2008 during a road widening project.  If someone could find the plans for that project it would show if it was actually designed that way or if it was just a fabrication error.

[Max Rockatansky]

Wasn't there something put out recently by Caltrans that external exit tabs would change the load capacity of the overhead gantries enough that it wasn't worth the cost to retrofit anything existing?