Civil Engineering Reference
In-Depth Information
Fig. 7.4 Route convergence and lane imbalances, I-95 southbound (Southern Connecticut)
Fig. 7.5 Examples of sharp
curves
and steep grades
Deficient Driveway Geometry: Commonly found where large entry areas are
without lane markings necessary to channel traf
c in an orderly way and where
the queue space for vehicles entering or leaving the driveway is insuf
cient to
prevent vehicles from spilling back onto the traf
c lanes (Fig.
7.8
).
Usually there is no provision for protected turning lanes or acceleration lanes
along the public road. This condition creates conflicts between vehicles resulting in
congested
flow and high crash rates. Pedestrian circulation is also problematic due
to pedestrian-vehicle con
fl
fl
icts.
