Random HWY Questions...

[UptownRoadGeek]

 
I was bored and thinking of all the random questions I had about highways, DOTS, roads, etc. and decided to post them to see if anyone could answer them for me. If you have any random questions feel free to add them.

1. Where is the stack on aaroads homepage photo thing?
2. For California to have such an extensive freeway network why is the signs so bad?
3. Why are traffic lights in Louisiana green?
4. Why do traffic lights in Houston have two red lights?
5. Why does Georgia pavement have that distinctive gray color?
6. Why does asphalt in most of Mississippi turn a brownish color when worn, except for the coastal areas?
7. Why does El Paso appear on a mileage sign 880 something miles away?
8. Why do bridges in Louisiana (new and old) make the car go tha-thuk tha-thunk tha-thunk?
9. What are the purpose of the slotted BGS's in Alabama?
10. What are the slotted BGS's in Alabama made of?
11. Why are most bridges over the Mississippi River (the lower mississippi at least) cantilever?
12. What are the rules to driving on Roosevelt Boulevard in Philly?
13. Why do Houston freeways make that whistling sound?
14. Why are BGS's in Florida rounded on the corners?
15. Why does Las Vegas rely so heavily on Botts Dots
16. Where can Botts Dots be found outside of California, Texas, Nevada, and parts of Louisiana?
17. Why does Birmingham, AL and Jackson, MS have big shiny VMS signs everywhere that are never on?
18. Who had the Michigan Left first?, Michigan or Louisiana?
19. Why doesn't I-75 meet I-95?
20. Why does the typical intersection in the NOLA area have 10+ traffic lights while anywhere else in LA may have 1 or 2 hanging on a wire?.. and does any other city have most of their traffic lights on pedestals like NOLA instead of hanging from wires or poles?

I know it is a lot of ?ions, but I was bored and I want to know the answers.

[yanksfan6129]

19. Answer number one: In theory, main interstates that are parallel to each other, then they should not me.
Answer number two: I don't know, perhaps they should just make the terminus of I-75 at I-95 by rerouting I-75 somehow.

[yanksfan6129]

2. Lack of funds? After all, if they have a lotta freeways, it would cost more to sign 'em all.

[yanksfan6129]

14. All rounded/routed corner BGS's seem to be that way for aesthetic purposes. After all, it is more expensive to do that then to not round/route them.

[Greybear]

7. Texas DoT probably did that to let drivers know just how big Texas really is.

[akotchi]

12.  Generally speaking, all six main lanes each way (three each roadway) on Roosevelt Blvd. are through.  At the intersections, left turns are made from the inner roadway; right turns, from the outer.  Crossovers are provided between the roadways in advance of the major intersections to provide ways to get to the proper roadway for the needed turns.  Turns from the side streets onto the Boulevard can, for the most part, be made to either roadway.  Some locations can only go to the inner, and at least two intersections have depressed bypasses for the inner roadways.

[WillWeaverRVA]

16. Where can Botts Dots be found outside of California, Texas, Nevada, and parts of Louisiana?

Hawaii and Guam use Botts Dots fairly extensively.

[corco]

The Puget Sound region uses tonnes of Botts Dots

[Chris]

1. Where is the stack on aaroads homepage photo thing?

I-105/I-110 interchange in Los Angeles.

[deathtopumpkins]

16: there's a list on the Botts Dots thread in the General Highway board.

3: Some municipalities choose to paint their signals colors... For example here newly installed signals are usually black in Newport News, and yellow in Hampton, though Newport News went through a phase where they used green so some signals reflect that.

7: I know that's been mentioned in the Control Cities thread in General Highway Talk.

Oh and yanksfan, couldn't you have fit those all into one post?  

[Michael]

3. Why are traffic lights in Louisiana green?

No idea, but in Central New York, we have black, green, and yellow.

4. Why do traffic lights in Houston have two red lights?

See this Wikipedia article.  For the visibility reason mentioned, we have one in Central New York at NY 3/NY 104 in Hannibal.

5. Why does Georgia pavement have that distinctive gray color?

Concrete highway? (Just a guess, never been there!)

8. Why do bridges in Louisiana (new and old) make the car go tha-thuk tha-thunk tha-thunk?

I'm guessing you're talking about the joints between segments.  Do they make the whistling sound too? (Again, never been there!)

9. What are the purpose of the slotted BGS's in Alabama?

Like in PA? See question 6 on this FAQ.

10. What are the slotted BGS's in Alabama made of?

Again, see the FAQ mentioned above.

13. Why do Houston freeways make that whistling sound?

I'm guessing they're concrete freeways. (never been there, either!)  They have grooves in them (like bridges), which I think get filled with air from tires covering them, and the air is forced out the sides of the grooves by the tire, making a whistling sound.  That's my theory, anyway!

14. Why are BGS's in Florida rounded on the corners?

Again, see the FAQ mentioned earlier.

15. Why does Las Vegas rely so heavily on Botts Dots

Less maintenance (I think).

16. Where can Botts Dots be found outside of California, Texas, Nevada, and parts of Louisiana?

Construction sites.

Hope this helps!

[UptownRoadGeek]

Thanks for the answers.

5. Why does Georgia pavement have that distinctive gray color?

Concrete highway? (Just a guess, never been there!)
It's asphalt but it has a color that I've only seen there. I guess it's the rocks

8. Why do bridges in Louisiana (new and old) make the car go tha-thuk tha-thunk tha-thunk?

I'm guessing you're talking about the joints between segments.  Do they make the whistling sound too? (Again, never been there!)
They don't whistle, just rattle. Also bridges in my area lack embankments and go straight up from the ground.

9. What are the purpose of the slotted BGS's in Alabama?

Like in PA? See question 6 on this FAQ.
I meant these

10. What are the slotted BGS's in Alabama made of?

Again, see the FAQ mentioned above.

Hope this helps!

Thanks again.

[Chris]

8. Why do bridges in Louisiana (new and old) make the car go tha-thuk tha-thunk tha-thunk?

Dilatation joints, means the bridge can shrink and expand somewhat under temperature differences.

[un1]

Ontario does the same thing, but Ontario also repaves over them, so on newer bridges they don't make that sound.

[FLRoads]

To answer your question #9, NOLANOLA504, the slotted signs are made out of a type of metal (I believe) and of course are used to allow wind to blow through the sign with more ease.

[Duke87]

Why do bridges in Louisiana (new and old) make the car go tha-thuk tha-thunk tha-thunk?

Simple viaduct style bridges all over the place are like that. The deal is, the bridge deck is built in sections. Each section spans from one support pier to the next (usually). At the pier, one section ends and another begins, and an expansion joint is put between them. That "tha-thuk" is your car going over those joints.

Expansion joints are necessary to prevent the deck from bucking or cracking due to materials expanding and contracting due to temperature changes, so this is unavoidable. You do obviously try and make the surface at the transition as smooth as possible, though.

[Alex]

5. Why does Georgia pavement have that distinctive gray color?
6. Why does asphalt in most of Mississippi turn a brownish color when worn, except for the coastal areas?
7. Why does El Paso appear on a mileage sign 880 something miles away?
9. What are the purpose of the slotted BGS's in Alabama?
13. Why do Houston freeways make that whistling sound?
14. Why are BGS's in Florida rounded on the corners?
16. Where can Botts Dots be found outside of California, Texas, Nevada, and parts of Louisiana?
17. Why does Birmingham, AL and Jackson, MS have big shiny VMS signs everywhere that are never on?
20. Why does the typical intersection in the NOLA area have 10+ traffic lights while anywhere else in LA may have 1 or 2 hanging on a wire?.. and does any other city have most of their traffic lights on pedestals like NOLA instead of hanging from wires or poles?

I know it is a lot of ?ions, but I was bored and I want to know the answers.

Answering a few things not answered or adding to the answers already mentioned:

5) it could be because Georgia uses diamond grinding techniques on their concrete freeways to extend their life. Diamond grinding takes the top most layer of the concrete, smoothing it out to prolong its life. The less downward force on pavement, the less chance of dips, potholes, and cracking.

6) probably because Mississippi uses red clay for many of its road bases. The red bleaches into the pavement over time.

7) like others have said, to show how truely wide Texas is.

9) they allow wind to pass through them, which helps with hurricanes I suppose. However this does not explain why some are found well north of the coast. There are two signs of this type along the Interstate 495 high-level bridge in Wilmington, Delaware and a couple in Newark, NJ as well.

13) probably because of grooved concrete.

14) a particular manufacturing technique? NC, VA, and NY use the same sign types. DE is phasing theirs out for MD-type signage with the corners.

16) Alabama used to use bot dots on all bridges and viaducts. They have phased these out over time, but they still can be found along Interstate 165 and other bridges, such as Alabama 59 over the Intracoastal Waterway.

17) you can extend that question to most areas!

20) pedestal signals are found in older urban areas, such as Philadelphia and Washington D.C. Considering NOLA's age and how it relates to those, its probably cost related in replacing them with more conventional signals.

That was fun. 

[PAHighways]

12. What are the rules to driving on Roosevelt Boulevard in Philly?

The inner roadways are the express lanes and the outer ones are for local traffic.  If you're going to be making a right turn, you enter the local roadway to do so, but for left turns you remain in the express lanes.

[UptownRoadGeek]

Why do bridges in Louisiana (new and old) make the car go tha-thuk tha-thunk tha-thunk?

Simple viaduct style bridges all over the place are like that. The deal is, the bridge deck is built in sections. Each section spans from one support pier to the next (usually). At the pier, one section ends and another begins, and an expansion joint is put between them. That "tha-thuk" is your car going over those joints.

Expansion joints are necessary to prevent the deck from bucking or cracking due to materials expanding and contracting due to temperature changes, so this is unavoidable. You do obviously try and make the surface at the transition as smooth as possible, though.

I understand the expansion joints in viaducts and long bridges, but unlike other states I've been to every single small crossing, overpass, ramp, etc. seems to be made that way here.

12. What are the rules to driving on Roosevelt Boulevard in Philly?

The inner roadways are the express lanes and the outer ones are for local traffic.  If you're going to be making a right turn, you enter the local roadway to do so, but for left turns you remain in the express lanes.

.

So if i'm in the local lanes and I need to get to the local lanes on the other side, I have to merge into the express lanes then turn left even if it means passing the next cross street?.

lol I though NOLA had some complicated driving laws.

[SSOWorld]

Why do bridges in Louisiana (new and old) make the car go tha-thuk tha-thunk tha-thunk?

These appear on older bridges - there are two in WI on I-94 westbound Milwaukee to Madison.  They stand out because they cross rivers and these rivers flooded last June - forcing the closure of the side of the freeway these connect.  They are older than the freeway itself

Hampton Roads Bridge Tunnel also has such - as does I believe some of the bridges over the Delaware River in Philly.

[PAHighways]

So if i'm in the local lanes and I need to get to the local lanes on the other side, I have to merge into the express lanes then turn left even if it means passing the next cross street?.

Yes, if you're wanting to access a business or a minor side street on the other side of the Boulevard.  Most intersections along it allow for left turns, but there are some that prohibit turns, which would require going to the next cross street to make a left turn and another to reach the local lanes.

[roadfro]

3. Why are traffic lights in Louisiana green?
15. Why does Las Vegas rely so heavily on Botts Dots
16. Where can Botts Dots be found outside of California, Texas, Nevada, and parts of Louisiana?
18. Who had the Michigan Left first?, Michigan or Louisiana?

Some answers:

3. In Reno, all older signals on Virginia Street in the downtown core are painted black (formerly maroon); new signals around downtown have a stylized look that mimic the newer style of street lamps that Reno has been using in street revitalization projects.  In areas of Las Vegas (notably Summerlin), traffic signal poles are painted a beigish/tanish color to better match the special style of street light poles used there.  I remember Anaheim having green signal poles on the street fronting Disneyland.  I'm sure there's numerous other examples.  It's purely an aesthetic thing that governments sometimes do to enhance the look of an area...in some cases, its used over the entire jurisdiction.

15. The Las Vegas does not get much rain--the average is typically around 4 inches per year (and less lately due to drought).  With little rain, all the grime and grease that accumulates on the road surface does not get cleaned off regularly by the rain.  This results in pavement markings getting obscured.  Thus, raised pavement markers (both Botts' Dotts and their reflective cousins) provide postive guidance where paint or marking film may not.  Las Vegas area entities save quite a bit on road paint this way as well (but that is partially offset by having to replace reflectors on a semi-regular basis).

16. A clarification on Nevada: You really only find Botts' Dotts in Las Vegas and maybe some highways/towns south of there.  Reflectors are used in combination with paint stripes in many other areas of Clark County.  Outside of Clark County (which is the southern tip of the state), raised pavement markers are typically not seen.  This is because smaller traffic volumes don't obscure the paint as much, as well as there being many areas where snow plows would shear them off the pavement.

18. Since its named "Michigan Left", I'd assume Michigan...

I understand the expansion joints in viaducts and long bridges, but unlike other states I've been to every single small crossing, overpass, ramp, etc. seems to be made that way here.

Every bridge is built with a minimum of two expansion joints, one near each abutment (i.e. one at each end).  Longer structures, such as viaducts and multi-span bridges, may be built with a number of expansion joints.  The purpose is as explained previously, to allow the bridge materials to expand and contract as temperatures change. 

In a well designed bridge, the driver will hardly notice when driving over an expansion joint.  In other cases, the engineers may not have adequately calculated the amount of expansion/contraction the bridge would experience, resulting in a much more prominent "tha-thunk".  There are also certain bridge designs where the expansion joint is noticeable simply due to the design--cantilever possibly comes to mind here.

There are other situations where this sound appears.  The I-515/US 95 viaduct just south of downtown Las Vegas comes to mind.  In this case, the viaduct spans weren't designed with enough of an arch to account for settling, so there are dips in the highway.  One hears a similar but gentler "tha-thunk" sound as you drive over the location of each set of supporting columns.

[OracleUsr]

You think that El Paso sign is something?  In Grande Prairie, AB, there's a sign for Alaska.  Even if that were the start of the AK highway, that would be 1500 miles...and Grand Prairie, AB, is nowhere near the start of the AK highway (thanks to Jim Teresco for pointing that sign out)

[akotchi]

I'd like to add two questions of my own here . . .

1.  What is the difference between an "alternate" route and a "business" route?  I know of a case in New Jersey where Alternate U.S. 1 was changed to Business U.S. 1 in Trenton.  Elsewhere in the state, Alternate U.S. 22 was changed to N.J. 122.  Is there a purpose to "Alternate" routes anymore?

2.  I've seen conversation elsewhere about not being able to sign toll roads as Interstate highways.  I know this is long-standing, but how, then, are current toll roads such as the Mass Pike, NY Thruway, and various northeastern Turnpikes signed as Interstates?

Thanks.  Wasn't sure where to put these questions, and they seemed too specific for separate threads.

[Bryant5493]

akotchi said:
2.  I've seen conversation elsewhere about not being able to sign toll roads as Interstate highways.  I know this is long-standing, but how, then, are current toll roads such as the Mass Pike, NY Thruway, and various northeastern Turnpikes signed as Interstates?

Bryant5493 says:
It's my understanding that the older freeways that you mentioned were "grandfathered" in.


Be well,

Bryant