The traffic on the design lane of a proposed four-lane rural interstate highway consists of 40% trucks. If traffic classification studies have shown that the truck factor (average number of ESAL per truck) can be taken as 0.45. The AADT (average annual daily traffic) on the design lane during the first year of operation is projected to be 1000. Traffic growth rate annually = 4% Design life = 20 years Reliability level = 95% Standard deviation = 0.45 Design a three-layer flexible pavement using the 1993 AASHTO procedure. The pavement structure will be exposed to moisture levels approaching saturation 20% of the time and it will take about one week for drainage of water. Effective CBR of the subgrade material is 7. CBR of the base and subbase are 70 and 22, respectively. Elastic resilient modulus for the asphalt mixture is 450,000 lb/in². The initial and terminal PSI are p; = 4.2 and pt = 2.5.

The traffic on the design lane of a proposed four-lane rural interstate highway consists of 40% trucks. If traffic classification studies have shown that the truck factor (average number of ESAL per truck) can be taken as 0.45. The AADT (average annual daily traffic) on the design lane during the first year of operation is projected to be 1000. Traffic growth rate annually = 4% Design life = 20 years Reliability level = 95% Standard deviation = 0.45 Design a three-layer flexible pavement using the 1993 AASHTO procedure. The pavement structure will be exposed to moisture levels approaching saturation 20% of the time and it will take about one week for drainage of water. Effective CBR of the subgrade material is 7. CBR of the base and subbase are 70 and 22, respectively. Elastic resilient modulus for the asphalt mixture is 450,000 lb/in². The initial and terminal PSI are p; = 4.2 and pt = 2.5.

Traffic and Highway Engineering

5th Edition

ISBN:9781305156241

Author:Garber, Nicholas J.

Publisher:Garber, Nicholas J.

Chapter13: Evaluating Transportation Alternatives

Section: Chapter Questions

Problem 24P

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