What superelevation rate would you use for a curve with a design speed of 100 km/h and a radius of 420 m? Round to the nearest whole percent. (b) A spiral transition curve is used to go from a normal crown slope with 2% cross-slopes to full superelevation for the curve described above. If the maximum difference in grade between the centerline and the edge is 1:200 and the roadway consists of two 3.6 m lanes, what is the minimum length of spiral? Round up to the next integral multiple of 20 m.

What superelevation rate would you use for a curve with a design speed of 100 km/h and a radius of 420 m? Round to the nearest whole percent. (b) A spiral transition curve is used to go from a normal crown slope with 2% cross-slopes to full superelevation for the curve described above. If the maximum difference in grade between the centerline and the edge is 1:200 and the roadway consists of two 3.6 m lanes, what is the minimum length of spiral? Round up to the next integral multiple of 20 m.

Traffic and Highway Engineering

5th Edition

ISBN:9781305156241

Author:Garber, Nicholas J.

Publisher:Garber, Nicholas J.

Chapter15: Geometric Design Of Highway Facilities

Section: Chapter Questions

Problem 8P

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