Interesting audio clip on Oklahoma's turnpikes

[bugo]

http://www.okhistory.org/okjourneys/turnpike.html

Has anyone ever heard anything else about exit ramps in cities being sharp to slow down enemies while entrance ramps were made wide and straight?

[bugo]

Highway ramps leading out were made wide and visible. To impede any invading Communists, off ramps into cities were fewer in number and were usually narrow with sharp turns to slow down incoming enemy traffic. Slowly across the entire country a comprehensive system of state and interstate highways began to emerge.

[Scott5114]

Apparently whoever designed I-44 and Lewis Avenue in Tulsa (and I-35 and S. 19th St. in Moore!) never got that memo.

So the question is, was the Wellston McDonalds designed to clog the Russians' arteries before they proceeded onward to Oklahoma City?

[bugo]

Apparently whoever designed I-44 and Lewis Avenue in Tulsa (and I-35 and S. 19th St. in Moore!) never got that memo.

The Onramp of Doom.

So the question is, was the Wellston McDonalds designed to clog the Russian's arteries before they proceeded onward to Oklahoma City?

In Soviet Russia, arteries clog you.

[mightyace]

Has anyone ever heard anything else about exit ramps in cities being sharp to slow down enemies while entrance ramps were made wide and straight?

No, but I've heard of this one:
Myth: The Insterstate Highway System was designed for emergency airstrips.

[Chris]

There were actually a lot of airstrips on European freeways, especially in eastern Europe and Germany. They just paved over the median with a removable barrier.

I can believe certain sections of Interstate may have been prepared as an emergency landing strip, but not with a systematic setup of straight sections every 5 miles. There is no country in the world with as many airports as the United States.

[J N Winkler]

There were actually a lot of airstrips on European freeways, especially in eastern Europe and Germany. They just paved over the median with a removable barrier.

Yup--I have a few pictures of Autobahn airstrips which the (British) Road Research Laboratory took in late 1945.

That audio clip is a really weak effort.

Edit:  It is an even weaker effort than I thought.  It says "Governor Murray" opened the Turnpike.  But actually Alfalfa Bill (of "three C's" infamy, despite which he still gets public facilities named after him in Oklahoma) had left office almost 20 years before the Turnpike opened.  I was under the impression that Governor Turner opened "his" turnpike.

[Scott5114]

That's correct. It was named in honor of him while he was still in office–half the legislature voted in favor of it to commemorate Turner's work in getting the turnpike built, while the other half voted in favor of it to allow motorists to know who was to blame for the tolls!

[agentsteel53]

Has anyone ever heard anything else about exit ramps in cities being sharp to slow down enemies while entrance ramps were made wide and straight?

I do not know, but I do know a lot of off-ramps are downhill, and on-ramps are uphill, which is entirely counterintuitive.  You want to slow down to get off the freeway, and speed up to get on.  But freeway design tends to prefer crossing streets to be the overpass, as opposed to the underpass, so we're stuck with trucks chugging their way onto the interstate, doing 30 when their lane ends and they have to merge in with traffic doing 65.

[J N Winkler]

There is not a preference for having cross roads under the freeway so much as it is a desire to avoid radical changes in the vertical alignments of roads which are used to access roadside businesses.  The reason for this is that it is not possible to provide access up an embankment, down a cutting (retained or not), or through bridge piers.  Failure to maintain an existing access normally ranks as a taking against the property which has to be paid for, and is often quite expensive in the case of commercial properties with significant entering and exiting traffic volumes which are critical to the viability of the businesses being accessed.  In urban areas there are many examples of freeways which fly over or under intersecting roads, but in both cases the elevation difference is developed parallel to the freeway centerline because the freeway by definition does not have access to abutting properties.  Whether the freeway flies over or under at a given location is usually governed by other considerations:  drainage, earthworks balance, extent and cost of traffic management required, consistency in geometric design, etc.

In Wichita the US 54 Kellogg freeway was extended past Rock Road as part of a single construction project, completed last November, with US 54 flying over Armour and under Rock Road.  The Kellogg freeway has three other flyunders (Oliver, Edgemoor, and Woodlawn) as well as eight flyovers, one of which is forced by the nearby Arkansas River crossing.  All of these grade separations were built in the last 25 years to a basic freeway plan which does not commit to an alignment consistently above grade, at grade, or below grade.  Kellogg has examples of all three along its length.

[agentsteel53]

a desire to avoid radical changes in the vertical alignments of roads which are used to access roadside businesses.

and here I thought it would be easier to build the freeway over an already-extant surface street, but it seems that elevating the surface street is more convenient?

[J N Winkler]

a desire to avoid radical changes in the vertical alignments of roads which are used to access roadside businesses.

and here I thought it would be easier to build the freeway over an already-extant surface street, but it seems that elevating the surface street is more convenient?

In rural areas where there is no development adjacent to the freeway, that often leads to better earthworks balance and a more consistent alignment on the freeway mainline.  But in cities where there is pre-existing development, it is usually more convenient to leave the surface street at or near its existing level.  The Kellogg flyunders were built by excavating below the level of the existing cross streets and building bridges to carry them over the freeway.

You can see the bridge for the Rock Road flyunder under construction (sans abutment backfill) in this Google Maps satellite extract:

http://maps.google.com/maps?q=Wichita,+KS&ie=UTF8&hq=&hnear=Wichita,+Sedgwick,+Kansas&ll=37.679382,-97.244233&spn=0.001093,0.003433&t=k&z=19