B-Unequal-Tangent Parabolic (Vertical) Curve: Example: A grade g1 of -2% intersects g2 of +1.6% at a vertex whose station and elevation are 87+00 and 743.24, respectively. A 400' vertical curve is to be extended back from the vertex, and a 600' vertical curve forward to closely fit ground conditions. Compute and tabulate the curve for stakeout at full stations. 83 +00 BVC (751.24) 84 +00 - 85 +00 A (747.24) ناوه شرق 40 1-86 +00 00+ 28- CVC (747.56) -2.00% Stations 00 +88 89 +00 +1.60% V (743.24) 00+ 06- 1-91 +00 B (748.04) Point A STA 85 +00: Elev. = 743.24+2 (2) = 747.24' Point B STA 90+00: Elev. = 743.24 +1.6 (3)=748.04' 00 + 26 وه ی 600 93 +00 EVC (752.84) ونا تسلیة شنانه و پوینتة نوت ده دوام وه Solution: The CVC is defined as a point of Compound Vertical Curvature. We can determine the station and elevation of points A and B by reducing this unequal tangent problem to two equal tangent problems. Point A is located 200' from the BVC and Point B is located 300' from the EVC. Knowing this we can compute the elevation of points A and B. Once A and B are known we can compute the grade from A to B thus allowing us to solve this problem as two equal tangent curves.

B-Unequal-Tangent Parabolic (Vertical) Curve: Example: A grade g1 of -2% intersects g2 of +1.6% at a vertex whose station and elevation are 87+00 and 743.24, respectively. A 400' vertical curve is to be extended back from the vertex, and a 600' vertical curve forward to closely fit ground conditions. Compute and tabulate the curve for stakeout at full stations. 83 +00 BVC (751.24) 84 +00 - 85 +00 A (747.24) ناوه شرق 40 1-86 +00 00+ 28- CVC (747.56) -2.00% Stations 00 +88 89 +00 +1.60% V (743.24) 00+ 06- 1-91 +00 B (748.04) Point A STA 85 +00: Elev. = 743.24+2 (2) = 747.24' Point B STA 90+00: Elev. = 743.24 +1.6 (3)=748.04' 00 + 26 وه ی 600 93 +00 EVC (752.84) ونا تسلیة شنانه و پوینتة نوت ده دوام وه Solution: The CVC is defined as a point of Compound Vertical Curvature. We can determine the station and elevation of points A and B by reducing this unequal tangent problem to two equal tangent problems. Point A is located 200' from the BVC and Point B is located 300' from the EVC. Knowing this we can compute the elevation of points A and B. Once A and B are known we can compute the grade from A to B thus allowing us to solve this problem as two equal tangent curves.

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 7P

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