Fastest and slowest states

Our speed limit is 70mph, and when I drove I would set the cruise for the width of the gauge needle under 80mph...so about 78ish I'd guess. Seemed to be about the middle of the pack for the most part, and since I would regularly pass cops I assume it's acceptable. LOL

 

Speed limit is 70 mph on Interstates here but if you stay around 70 mph everyone else will pass you by. On two lane roads it is 55 mph but most people(me) go 60-62 mph. In the city limits I know people who have been ticketed for going 5 mph over what the street speed limit is.

 

There is a new toll road between in Texas running between Austin and San Antonio that has a speed limit of 85 (eighty-five) MPH.

 

One seldom thought about consequence of the 55 mph speed limit was cost cutting on freeways. A 100 MPH spec freeway costs a LOT more to build than a 55 MPH freeway. View distance (less curves and elevation changes), on and off ramp length and freeway strength are drastically reduced with a 55 MPH spec. Now we want to speed back up but we will damage the pavement, damage our vehicles and have more wrecks.

One of the safest freeways around is south of LA which was designed for a future 100 MPH limit. 80 MPH on that freeway is a relaxing cruise. Up north through Oakland is a freeway that followed the old two lane 45 MPH from the 40's. 80 MPH through there is dangerous to insane depending on the traffic.

Hopefully people will realize this if we get a 75 mph state speed limit. Some freeways were never intended for that speed.

 

I wonder if that has anything to do with our freeways and other roads being in a constant state of repair. Not that it's much of an increase, though... people have been saying since well before my birth that Michigan has two seasons: winter and road construction.

 

Road construction is a very technical subject. I will try not to be a "road geek".
Turning, stopping and acceleration are forces in a horizontal plane. Generally only the top few inches get stress from this.
Weather, ground water, shifting soil, soil compaction, varying loads (one car at 80 vs 500 stopped trucks at full load) and thermal expansion are the larger part of the equation.
This may help explain:
http://www.texasfreeway.com/Dallas/newsflash/loop9_soil_conditions.shtml
One local freeway was supposed to go down 28 - 30 ft and replace the dirt with crushed granite and binders for a 75 MPH speed spec. That was reduced to 15-16 ft when the speed spec was reduced to 55 MPH. We now have cracks and waves in the previously glass smooth freeway because it has insufficient support.

 

OK, gotta go geek on ya.
http://www.highwaysmaintenance.com/design.htm

Speed has a vertical loading component because suspension does not put 100% equal loading across the surface. A bump you cannot see or feel at 50 MPH becomes a large force at 100 MPH. Ask any racer.