Question

Problem 2. (30 points) You are asked to design a vertical curve that connects -4% and +1% grades along a roadway section with a design speed of 65 mi/h. It is determined that the PVI should be located at sta 10+25 and elevation of 175 ft. You are directed to adopt in your design the minimum requir length of curve that satisfies the design speed. Based on these inputs, determine the followi. a) Length of curve; b) Station and elevation of the PVC; c) Station and elevation of the lowest point of the curve; d) Mid-curve offset. (5 points)

Answer 1

Given, g, - 4% K7157. 92 +1% Denge speed (v) 65 mph ..Ao 82-81-1-(4), sy. From AASTHO exhibli-3-75, for 12 65 mph. A length of the Sag Curre ya kia 15785 785 ft Station of Pria Sta (10+25) station of Prce sta PVI - % Sta (10725) - 785 1025 - 39969 2 632.5 Sta (6+32-5)] Station of PNTo sta pre te 2 Sta (6+325) + 165 2 63215 +785 2 14170 s 2 sta ( 14+17.5)]

Euration of Pvc Een of erit 8, 175 + 0.01%7&s [19013 ft) Eler of PNS + 922 Eleration of PVT 2 175+ 0.01x 785 - 178.93 ft Equation of Carre elevation Ya ant butc z axit baty ar 9 I- 2 al are in statim Too ft a stalim Yo Eur of pre I 190.7 2-4 Lin statim. 285 7.85 iae 1-(-4) 2x 7.35 032 © To determine LY the 0.32m-an t190.7] of station da Coordinates from pvc lowest point, we have to do at too ft interrad da 1.32n- Antig0.7 2.0 0642-420 X 6.25 → a station of comest point o sta (6t32.5) + 6. 25x100 2632.5 + 625 o 1257.5 afste (194 57.5)) i Ebration of lowest point 0.32 (6,2%) -4/6-45) +18017 178.2 fH wordinates of mid carre, de 22 - 3.925 in mind corre offsel - 0.32 (3.925)- 9(3.925) + 1907 (179.93 ft