The Indiana Department of Transportation (INDOT) has been using ESAL (Equivalent Single Axle Load) values for pavement design. The current ESAL values were obtained in the late 1970. However, truck deregulation and higher allowable maximum loads have increased the 1970's values. Updated ESAL values are needed for better road designs. The 1998 and 1999 traffic data from the all Weight-in-Motion (WIM) stations were obtained and used to compute updated ESAL values for multiple unit trucks (Class 9/F-9) and single unit trucks (Class 5, 6 and 7). Statistical analyses indicated that average ESAL values for 1998 and 1999 are statistically the same, but the average ESAL values for interstates roads and non-interstates roads are not all statistically the same. Some WIM stations were deleted for definite calibration problems. Due to other calibration deficiencies, the data was refined before final ESAL computations. Then the following ESAL values were computed and recommended to be used for future INDOT road designs: For Multiple Unit Trucks (Class 9): a) 1.3 ESAL/Truck for flexible pavements b) 2.0 ESAL/Truck for rigid pavements For Single Unit Trucks (Class 5, 6 & 7): a) 0.6 ESAL/Truck for flexible pavements b) 0.9 ESAL/Truck for rigid pavements

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ESAL, Equivalent Single Axle Loads, Pavement Design, WIM, SPR-2331

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Performing Organization

Joint Transportation Research Program

Publisher Place

West Lafayette, IN

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