Performance and cost-effectiveness of air disc brakes and air drum brakes for truck semi-trailers in different road and speed conditions

Vincent Michael Ampadu (1) , Anas Alrejjal (2) , Khaled Ksaibati (3)
(1) Department of Civil & Architectural Engineering, University of Wyoming, 1000 E University Avenue, Laramie, WY 82072, US , United States
(2) OHM-Advisors, 209 10th Avenue South Nashville, Tennessee, US , United States
(3) Wyoming Technology Transfer Center, Department of Civil & Architectural Engineering, University of Wyoming, 1000 E University Avenue, Laramie, WY 82071, US , United States


This study uses TruckSimTM to model disc brakes and drum brakes on a fully loaded truck semi-trailer to study the performance of each brake type as downgrades and speeds vary. The brake performance is measured based on braking distance. A simplified economic comparison based on life cycle cost analysis to determine which road and vehicle conditions give rise to the cost-effectiveness of disc brakes is performed. The studies suggest that disc brakes shorten braking distances by 10-20%. They also suggest that the percentage reduction in braking distance as speed increases and downgrade gets steeper is approximately 12-19%. Evidence is provided that trucking companies operating their vehicles in steep terrain and at high speeds with disc brakes could benefit from 12-80% in long-term cost savings. Finally, at the societal level, by preventing crashes arising from rear-end collisions and runaway truck incidents, disc brakes save at least $649 million annually.

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Vincent Michael Ampadu (Primary Contact)
Anas Alrejjal
Khaled Ksaibati
Ampadu, V. M., Alrejjal , A., & Ksaibati , K. (2023). Performance and cost-effectiveness of air disc brakes and air drum brakes for truck semi-trailers in different road and speed conditions. Journal of Sustainable Development of Transport and Logistics, 8(1), 24–42.

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