Traffic in the US is going to get worse — but things are changing
https://transportist.org/2016/04/19/21-strategies-to-solve-congestion/
21 Strategies to Solve Congestion
https://www.ncga.state.nc.us/documentsites/committees/21stcenturytransportation/prioritization-best%20practices-efficiency/presentations/mobility_report_2007_wappx.pdf
THE 2007 URBAN MOBILITY REPORT
David Schrank
Associate Research Scientist
and
Tim Lomax
Research Engineer
These studies do not solve the road traffic problems. In fact, they make them even worse. A congestion occurs when cars do not move at all. The problem is certainly due to mismatch of incoming traffic to outgoing traffic. If the traffic is equal, there is no chance of any congestion at all. The cars may move slowly, but there is no congestion.
This simple reality seem to escape a lot of these authors and researchers. Another important fact is that, the traffic handling of a road is not dependent on the speed of the cars. The number of cars moving through a road at a fixed time internal is the same no matter how fast the cars move through the road.
The major cause of congestion are the road junctions. In a 4-way junction, controlled by traffic lights, in the worst case, 4 inflows want to get out though 1 outflow. This problem is similar to network hubs. The solution is to deploy switches.
For road junctions, you do not build flyovers for all vehicles and at normal speeds. Design underpasses for cars only at slow speed. You will solve a lot of congestion problems with the minimum costs and area required.
There is no need for any exotic technology. Just deploy underground car parks at the junctions. We can start by deploying underpasses only, i.e. 2 layers of roads.
Of course, the layers of roads proposed by Elon Musk is the final solution but many cities cannot afford to wait for the technology to mature.
You can refer to my full paper uploaded at researchgate.
https://www.researchgate.net/publication/321110572_An_Optimum_Urban_Road_Junction_Design
