curve data 3

[CivilTyro]

Someone please help me understand the curve data of a curb, plz?

Curve data #1
R=10'
L=15.85'
Delta
starting angle 36deg 28min 57sec
end angle 127deg 16min 52sec
total angle 90deg 47min 55sec

what delta should I use to calculate my Tangent length
T= R*tan(delta)/2
Also, what is T and its significance in construction?


Also what delta should I use for finding tangent length for the following

curve date #2
R=67
L=142.39
Delta
starting angle 269deg 20min 5sec
End angle 31deg 6min 15sec
total angle 121deg 46min 10sec

Thanks a lot in advance.

 

[Maury]

Delta#1 = 90d47m55s
Delta#2 = 121d46m10s

These are the differences between the end angle and the start angle, which are the bearings of the tangents.

T = tangent lengths of the curves. These lengths are sometimes needed for staking but probably aren't necessary fot the small curves described here, where a steel or fiberglass tape can be used to swing an arc.

These small curves are probably used for curb returns at an intersection. I wouldn't have bothered calculating all of the curve data for this application, just provided a location for the center point and noted the radius. The full curve data is needed for a centerline alignment.

 

[Hoagie]

http://www.sd-w.com/civil/highway_curve.html