Speeding is common everywhere. We act so surprised that people do it so much but ignore it in most applications. 65 MPH speed limits on the highway are impossible to enforce because everyone is going over 65. You have to be going at least 80 to get a speeding ticket in a 65. This is indicative of a huge problem in Transportation engineering schools and design guidelines like the AASHTO Green book I mentioned before on this blog.
Who are we kidding with this?
Like other disciplines of engineering factors of safety are used in all aspects including design speeds. A factor of safety is the practice of designing something for higher levels of capacity than they are expected to reach. For example when designing a building if the expected loads are say 800 pounds you design for 1,000 pounds. The difference is that the loads will not decide to increase to 1,000 pounds when you do this. In road design you generally add on about 15 mph to the posted speed limit. So a 65mph road is geometrically designed(sight distances, curve radii, lane widths) for 80 mph. People usually drive at 80 mph on the highway.
Speeding happens because of the way we design our roads. Enforcement of traffic laws can play a large role in compliance but more importantly roads themselves control speeds people use them. If we want people to drive a certain speed we should design the street for that speed. Hopefully the letter AASHTO sent to USDOT is a sign of things to come from them and publishers of transportation engineering books.
heavily signalized
No signs whatsoever
For the most part I do not like signs in general. I think they do very little to increase safety and tend to decrease overall driver awareness. Where I work on Roosevelt Island I think they should get rid of all the traffic signs, save for one sign when you enter the island that tells you to drive counter clockwise around the island. Hans Monderman did this in Drachten Netherlands where he removed all the signs in a village except for one sign before you enter the village that says “no road signs ahead, speed limit 30kmh”. Traffic flowed smoother with a sharp decrease in crashes. It is really quite impressive and radical idea that worked.
relaxed cycling
you haven’t posted anything in a while, bub.