(obstructions) (3-26)
FRAME 3-27.
Obstructions are factors which restrict the type, amount, or speed of traffic flow. They are always recorded
Any factors which restrict traffic flow are considered _____________________ and are ___________________
(80; 60; 6) (3-56)
FRAME 3-57. REVIEW FRAME.
Before further discussing the bridge symbol, let's briefly review obstructions; the factors which restrict the type
and amount or speed of traffic flow and which are always recorded on the route reconnaissance overlays. So far, the
following features have been classified as obstructions:
a. Curves whose radii of curvature are 25m or less.
b. Gradients (slopes) of 7% or greater.
c. Reduction in traveled way widths which are below minimum standards prescribed for the type traffic flow
(single or double, wheeled or tracked.) Minimum widths were defined as:
d. Overhead clearances which are less than 4.3m.
3-55