What is the elevation of the point of vertical tangency for an equal-tangent sag vertical curve with the following given information?
G₁ = -2%, G₂ = +4%, L= 300 ft, PVC Sta = 100+00, PVC Elev = 100.00 ft

Question

Quizplus · Accepted Answer

the elevation of the point of vertical tangency for the given equal-tangent sag vertical curve is 103 ft. Solution: Use the general parabolic formula for a vertical curve y = ax² + bx + c Where a = (G₂ - G₁ )/2L Given, G₁ = -0.02 G₂ = +0.04 L = 300 ft a = (0.04 - (-0.02))/2(300) = 0.0001 x = curve length = L = 300 ft b = G₁ = -0.02 c = PVC elevation = 100 ft y = 0.0001 (300) ² + (-0.02) (300) + 100 = 9 - 6 + 100 = 103 ft

What Is the Elevation of the Point of Vertical Tangency