Calculate the super-elevation required for a horizontal curve on a two-lane, two- way highway with 60 mph design speed, and a 1200 ft. radius curve. What is the required length of the spiral curve? If the lane width is 12 ft, and the cross (side) slope of the crown section is 2.0%, draw to a convenient scale the progress of pavement edges to attain the superelevation. Revolve the pavement about its
a. Inside edge. b. Outside edge c. Centerline