an interstate highway pavement composed of a hma surface course, a cement treated base course, and a sand–gravel subbase is to be designed for an esal of 1.2*10^6.the quality of drainage is considered fair because water can be removed from the subbase within a week. however, there is a large amount of precipitation, so more than 25% of the time the pavement will be exposed to moisture levels approaching saturation. the material properties are as follows: effective roadbed soil resilient modulus = 5,500 psi, resilient modulus of subbase = 15,000 psi, unconfined compressive strength of cement-treated base at 7 days = 500 psi, and resilient modulus of hma = 4.3*10^5 psi. assuming a minimum thickness for hma, determine the thicknesses of the surface, base,and subbase courses required. Assuming a minimum thickness for HMA, determine the thicknesses of the surface, base,and subbase courses required.

an interstate highway pavement composed of a hma surface course, a cement treated base course, and a sand–gravel subbase is to be designed for an esal of 1.210^6.the quality of drainage is considered fair because water can be removed from the subbase within a week. however, there is a large amount of precipitation, so more than 25% of the time the pavement will be exposed to moisture levels approaching saturation. the material properties are as follows: effective roadbed soil resilient modulus = 5,500 psi, resilient modulus of subbase = 15,000 psi, unconfined compressive strength of cement-treated base at 7 days = 500 psi, and resilient modulus of hma = 4.310^5 psi. assuming a minimum thickness for hma, determine the thicknesses of the surface, base,and subbase courses required. Assuming a minimum thickness for HMA, determine the thicknesses of the surface, base,and subbase courses required.

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 15P

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