PRIN.OF HIGHWAY ENGINEERING&TRAFFIC ANA.
7th Edition
ISBN: 9781119610526
Author: Mannering
Publisher: WILEY
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Chapter 3, Problem 14P
To determine
A satisfactory curve length and check the adequacy of the existing curve in light of the reconstruction design.
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A curve of radius 76 m and e = 0.08 is located at a section of an existing rural highway, which restricts the safe speed at this section of the highway to 50% of the design speed. This drastic reduction of safe speed resulted in a high crash rate at this section. To reduce the crash rate, a new alignment is to be designed with a horizontal curve. Determine the minimum radius of this curve if the safe speed should be increased to the design speed of the highway. Assume fs = 0.17 for the existing curve. The new curve is to be designed with the same superelevation
A highway reconstruction project is being undertaken to reduce accident rates. The reconstruction involves a major realignment of the highway such that a 50 mph design speed is attained. At one point on the highway, an 800 ft equal tangent crest vertical curve exists. Measurements show that at 3-52 stations from the PVC, the vertical curve offset is 3 ft. Assess the adequacy of this existing curve in light of the reconstruction design speed of 60 mph and, if the existing curve is inadequate, compute an adequate curve length.
A curve of radius 250 ft and e 0.08 is located at a section of an existing rural highway, which restricts the safe speed at this section of the highway to 50% of the design speed. This drastic reduction of safe speed resulted in a high crash rate at this section. To reduce the crash rate, a new alignment is to be designed with a horizontal curve. Determine the minimum radius of this curve if the safe speed should be increased to the design speed of the highway. Assume fs= 0.17 for the existing curve, and the new curve is to be designed with e = 0.08
Chapter 3 Solutions
PRIN.OF HIGHWAY ENGINEERING&TRAFFIC ANA.
Ch. 3 - Prob. 1PCh. 3 - Prob. 2PCh. 3 - Prob. 3PCh. 3 - Prob. 4PCh. 3 - Prob. 5PCh. 3 - Prob. 6PCh. 3 - Prob. 7PCh. 3 - Prob. 8PCh. 3 - Prob. 9PCh. 3 - Prob. 10P
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