A northbound direction on an interstate highway consists of four lanes of flexible pavement. It is conservatively designed with a 10-inch sand-mix asphaltic surface, 10-crushed stone base, and a 10-inch crushed-stone subbase (all drainage coefficients are 1.0). The subgrade CBR is 3, the overall standard deviation is 0.4, and the reliability is 95%. The initial PSI is 4.6 and the final PSI is 2.5. Daily total northbound road traffic consists of 51,000 cars (each with two 2-kip single axles), 840 buses (each with two 20-kip single axles), and 1,000 heavy vehicles (each with one 12-kip single axle and two 34-kip tandem axles). How many years was this pavement designed to last?

A northbound direction on an interstate highway consists of four lanes of flexible pavement. It is conservatively designed with a 10-inch sand-mix asphaltic surface, 10-crushed stone base, and a 10-inch crushed-stone subbase (all drainage coefficients are 1.0). The subgrade CBR is 3, the overall standard deviation is 0.4, and the reliability is 95%. The initial PSI is 4.6 and the final PSI is 2.5. Daily total northbound road traffic consists of 51,000 cars (each with two 2-kip single axles), 840 buses (each with two 20-kip single axles), and 1,000 heavy vehicles (each with one 12-kip single axle and two 34-kip tandem axles). How many years was this pavement designed to last?

Traffic and Highway Engineering

5th Edition

ISBN:9781305156241

Author:Garber, Nicholas J.

Publisher:Garber, Nicholas J.

Chapter19: Design Of Flexible Highway Pavements

Section: Chapter Questions

Problem 16P

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