anyone know Formula to Convert Degree of Curve to a Radius 1

[jiminem2]

I'm reproducing an old set of highway plans into civil 3d, instead of listing the radius on the curves they have "degree of curve", they also have delta angle ect ect. but I really need the formula for degree of curve to radius. please help!
thanks

 

[CarlB]

The "degree" of a curve is the central angle from beginning to end of 100 feet along the curve. But there are "arc" and "chord" definitions for "degree" (D), depending if the 100 feet is along the arc or the chord.

By arc definition:

100/D=(2 x pi x R)/360


By chord definition:

R=50/(sin D/2)

 

[chicopee]

Gee! that information should have been provided in his freshmen surveying course.