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General Guide to RoadPlus - 4.0.0en
Glossary
Slope
The slope is next to the verge. It links the road level with the
original ground. Its slope ratio is usually higher than the one of
the verge. For a fill, the slope direction corresponds to the one
of the verge. For a cut, it is the opposite direction.
Spiral
A gradual horizontal transition from a tangent to a curve or two
curves of different radii; optional for roads, required for
railroads.
Spiral In
A gradual horizontal spiral transition from a tangent to a curve
(R
1
=
∞
, R
2
= n, parameter A).
Spiral Out
A gradual horizontal spiral transition from a curve to a tangent
(R
1
= n, R
2
=
∞
, parameter A).
Station
The cumultative distance along the horizontal alignment,
frequently but not always starting at zero. Also called chainage.
Parabola
A parabolic arc. Exists only on vertical alignments.
Profile
See cross section
Reference Point
A second point often marked nearby the catch point or other
point of interest since the catch point is often gone after the
first earth movements. The stake is typically marked with the
information that allows the user to replace the point of interest
and re-create the slope information. Also known as the offset
point.
Roadway
See carriage way
Shoulder
See verge