NEW A4 Parclo and ramp design.

[Indyroads]

Recently I have noticed a new trend with CalTrans engineering design regarding directional and loop ramps where they intersect cross streets.


http://tinyurl.com/newcaliparclo

This is an example of what I am talking about. The ramps no longer have their wide sweeping geometry where they meet the intersecting street. Drivers now have to make a more deliberate right turn on to the ramps in order to enter the freeway, rather than just digerving like on the previous design. Does anyone have any insight into this design change. They are starting to become more commonplace

another example:

http://tinyurl.com/elverta99

and one shown in the construction phase:

http://tinyurl.com/70FeatherRiv

[cl94]

Few reasons:

1. Reduce turn speeds and curve radii to improve safety. Many places are taking out channelized turns for this reason.
2. Going along with the above, increases pedestrian safety
3. At least one of those used to be a tight cloverleaf. They removed the exit loops.

[kkt]

The two finished examples have bike lanes on the street.  Perhaps they're encouraging motor vehicles turning right to move into the turn lane at one spot, rather than drifting over gradually just anywhere.

[jakeroot]

Washington has done this on a couple of occasions in the Tri-Cities. A previous thread came to the conclusion that these loops are sharpened to increase pedestrian safety.

https://www.aaroads.com/forum/index.php?topic=14604.msg2038236#msg2038236