ABSTRACT
ABSTRACT: BNSF Railway is one of the largest freight rail transportation companies in the United States. A major concern facing the company today is increasing maintenance costs due to heavier loadings and challenging track conditions. This paper focuses on coal dust fouling in the Powder River Basin of Wyoming, and the use of hot-mix asphalt (HMA) in lieu of granular sub-ballast on intermodal line between Chicago, Illinois and Los Angeles, California. It is believed ballast fouling decreases the track’s ability to carry load and is detrimental to its strength and stability. The challenge is recognizing the material causing the fouling condition and identifying areas with significant fouling levels where the structure may be compromised. Ground penetrating radar was used to aid in marking possible trouble areas and gradation analyses were performed to establish a condition rating for each location. As part of BNSF’s long term HMA evaluation, a field program to test the condition of several underlayment sites was undertaken and the overall quality and performance of HMA is discussed.
