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Odd signalized intersections

Started by tolbs17, March 23, 2021, 07:06:50 PM

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mrsman

Quote from: HTM Duke on April 27, 2021, 03:21:45 AM
Quote from: Caps81943 on April 27, 2021, 12:44:35 AM
This one in NoVA (Herndon) that I randomly found one day is just between a very minor artery (25 mph) and a quiet neighborhood street:

https://www.google.com/maps/@38.9857389,-77.397046,3a,82.5y,186.74h,89.59t/data=!3m6!1e1!3m4!1s-2s9MD4izqDLTkZrT8coeA!2e0!7i16384!8i8192

Looking at Google, I see that there's an elementary school near the east end of Builder's Rd.  I'd wager a guess and say that signal was installed to make it easier for buses and other school traffic to reach and depart from said school.

Many intersections that do not have enough traffic to normally justify a signal are placed near schools so that it is perceived as being safer for children to cross the street. And even if Crestview isn't all that busy, it could still be a street with a decent amount of speeding


Big John

Quote from: HTM Duke on April 27, 2021, 03:21:45 AM
Quote from: Caps81943 on April 27, 2021, 12:44:35 AM
This one in NoVA (Herndon) that I randomly found one day is just between a very minor artery (25 mph) and a quiet neighborhood street:

https://www.google.com/maps/@38.9857389,-77.397046,3a,82.5y,186.74h,89.59t/data=!3m6!1e1!3m4!1s-2s9MD4izqDLTkZrT8coeA!2e0!7i16384!8i8192

Looking at Google, I see that there's an elementary school near the east end of Builder's Rd.  I'd wager a guess and say that signal was installed to make it easier for buses and other school traffic to reach and depart from said school.

Apparently met the school signal warrant.

tolbs17

#27
I think this junction can do without a signal. When the northwest bypass gets built, they should definitely remove it. AADT is low enough to just have stop signs.

The other one should stay signalized because of the factory that's there.

Also, what I find funny here in Wilson, that this junction is signalized and only has one lane.

mrsman

Quote from: tolbs17 on May 01, 2021, 05:49:51 PM
I think this junction can do without a signal. When the northwest bypass gets built, they should definitely remove it. AADT is low enough to just have stop signs.

The other one should stay signalized because of the factory that's there.

Also, what I find funny here in Wilson, that this junction is signalized and only has one lane.

For the second one, even if traffic is low, traffic coming off the off-ramp will have a hard time making a left because of the hill.  It will be hard for them to see cross-traffic.

So either a signal or an all-way stop seems necessary.

tolbs17

Quote from: mrsman on May 04, 2021, 07:54:59 AM
Quote from: tolbs17 on May 01, 2021, 05:49:51 PM
I think this junction can do without a signal. When the northwest bypass gets built, they should definitely remove it. AADT is low enough to just have stop signs.

The other one should stay signalized because of the factory that's there.

Also, what I find funny here in Wilson, that this junction is signalized and only has one lane.

For the second one, even if traffic is low, traffic coming off the off-ramp will have a hard time making a left because of the hill.  It will be hard for them to see cross-traffic.

So either a signal or an all-way stop seems necessary.
One in Wilson, right?

mrsman

Quote from: tolbs17 on May 04, 2021, 07:56:54 AM
Quote from: mrsman on May 04, 2021, 07:54:59 AM
Quote from: tolbs17 on May 01, 2021, 05:49:51 PM
I think this junction can do without a signal. When the northwest bypass gets built, they should definitely remove it. AADT is low enough to just have stop signs.

The other one should stay signalized because of the factory that's there.

Also, what I find funny here in Wilson, that this junction is signalized and only has one lane.

For the second one, even if traffic is low, traffic coming off the off-ramp will have a hard time making a left because of the hill.  It will be hard for them to see cross-traffic.

So either a signal or an all-way stop seems necessary.
One in Wilson, right?

Yes.

tolbs17

Quote from: mrsman on May 04, 2021, 10:36:22 AM
Quote from: tolbs17 on May 04, 2021, 07:56:54 AM
Quote from: mrsman on May 04, 2021, 07:54:59 AM
Quote from: tolbs17 on May 01, 2021, 05:49:51 PM
I think this junction can do without a signal. When the northwest bypass gets built, they should definitely remove it. AADT is low enough to just have stop signs.

The other one should stay signalized because of the factory that's there.

Also, what I find funny here in Wilson, that this junction is signalized and only has one lane.

For the second one, even if traffic is low, traffic coming off the off-ramp will have a hard time making a left because of the hill.  It will be hard for them to see cross-traffic.

So either a signal or an all-way stop seems necessary.
One in Wilson, right?

Yes.
But the other side is not signalized.

US 89

Quote from: tolbs17 on May 04, 2021, 11:39:03 AM
Quote from: mrsman on May 04, 2021, 10:36:22 AM
Quote from: tolbs17 on May 04, 2021, 07:56:54 AM
Quote from: mrsman on May 04, 2021, 07:54:59 AM
Quote from: tolbs17 on May 01, 2021, 05:49:51 PM
I think this junction can do without a signal. When the northwest bypass gets built, they should definitely remove it. AADT is low enough to just have stop signs.

The other one should stay signalized because of the factory that's there.

Also, what I find funny here in Wilson, that this junction is signalized and only has one lane.

For the second one, even if traffic is low, traffic coming off the off-ramp will have a hard time making a left because of the hill.  It will be hard for them to see cross-traffic.

So either a signal or an all-way stop seems necessary.
One in Wilson, right?

Yes.
But the other side is not signalized.

So? That side doesn't have the visibility issues nearly to the same extent.

tolbs17

Should all exit ramps (that have one signal on whatever side) have signals on both sides?

hotdogPi

Quote from: tolbs17 on May 08, 2021, 11:04:06 PM
Should all exit ramps (that have one signal on whatever side) have signals on both sides?

No. Having two signals makes it impossible to have coordinated signals in both directions simultaneously.
Clinched, minus I-93 (I'm missing a few miles and my file is incorrect)

Traveled, plus US 13, 44, and 50, and several state routes

I will be in Burlington VT for the eclipse.

Mapmikey

Quote from: tolbs17 on March 26, 2021, 09:07:36 PM
https://www.google.com/maps/@35.8178579,-77.4524257,3a,75y,328.34h,78.8t/data=!3m6!1e1!3m4!1srdRObN8XWjEkB-vKOIRYMQ!2e0!7i13312!8i6656

I'm pretty sure this intersection was signalized (maybe not) before, but it only goes back to 2002. The freeway section opened in 1998.

AADT is too low to make it a 4-way stop or a roundabout.

Pretty sure the US 64-NC 42 jct was not signalized.  It wasn't in the late 1970s.

roadfro

Quote from: 1 on May 09, 2021, 08:20:37 AM
Quote from: tolbs17 on May 08, 2021, 11:04:06 PM
Should all exit ramps (that have one signal on whatever side) have signals on both sides?

No. Having two signals makes it impossible to have coordinated signals in both directions simultaneously.

Say for like a standard diamond interchange? It's odd to have a signal on one side but not the other, but that doesn't mean you have to have a signal on both sides.

Having signals at both ramp intersections doesn't make it impossible to have coordinated signals. But you might not be able to both directions of the arterial road flowing at the same time through the interchange–but a few diamond interchange phasing schemes exist to minimize the stops and delays associated with interchange signals. However, in many implementations of coordinated signal corridors, you don't always have both directions going simultaneously anyways (lead-lag phasing generally results in better signal progression in a corridor where left turn phasing is frequently used)
Roadfro - AARoads Pacific Southwest moderator since 2010, Nevada roadgeek since 1983.

tolbs17

Quote from: roadfro on May 09, 2021, 07:12:44 PM
Quote from: 1 on May 09, 2021, 08:20:37 AM
Quote from: tolbs17 on May 08, 2021, 11:04:06 PM
Should all exit ramps (that have one signal on whatever side) have signals on both sides?

No. Having two signals makes it impossible to have coordinated signals in both directions simultaneously.

Say for like a standard diamond interchange? It's odd to have a signal on one side but not the other, but that doesn't mean you have to have a signal on both sides.

Having signals at both ramp intersections doesn't make it impossible to have coordinated signals. But you might not be able to both directions of the arterial road flowing at the same time through the interchange–but a few diamond interchange phasing schemes exist to minimize the stops and delays associated with interchange signals. However, in many implementations of coordinated signal corridors, you don't always have both directions going simultaneously anyways (lead-lag phasing generally results in better signal progression in a corridor where left turn phasing is frequently used)
See I-795/US-301 in Wilson, NC.

webny99



tolbs17

Quote from: mrsman on May 04, 2021, 07:54:59 AM
Quote from: tolbs17 on May 01, 2021, 05:49:51 PM
I think this junction can do without a signal. When the northwest bypass gets built, they should definitely remove it. AADT is low enough to just have stop signs.

The other one should stay signalized because of the factory that's there.

Also, what I find funny here in Wilson, that this junction is signalized and only has one lane.

For the second one, even if traffic is low, traffic coming off the off-ramp will have a hard time making a left because of the hill.  It will be hard for them to see cross-traffic.

So either a signal or an all-way stop seems necessary.
So, this one should also be signalized


tolbs17


tolbs17


jakeroot

I've never understood why S 12th & Pine in Tacoma was signalized. Pine is a neighborhood street with mostly unsigned intersections, yet it gets a full signal at S 12th.

tolbs17


kphoger

Keep right except to pass.  Yes.  You.
Visit scenic Orleans County, NY!
Male pronouns, please.

Quote from: Philip K. DickIf you can control the meaning of words, you can control the people who must use them.


kphoger

Keep right except to pass.  Yes.  You.
Visit scenic Orleans County, NY!
Male pronouns, please.

Quote from: Philip K. DickIf you can control the meaning of words, you can control the people who must use them.

tolbs17




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