Locating Railroad Track Bed Subsurface Defects Utilizing Nondestructive Remote Sensing Technologies

The railroad is a vital transportation link with tracks traversing thousands of miles throughout the United States.<br>When this link fails, the resultant damage costs millions of dollars. Track failure, attributed to moisture trails and<br>erosion voids in the rock ballast and subsoils that support the tracks, slowly deteriorate the railbed to a critical<br>point in which iron rail shifts occur. All railroad lines experience failures on a regular basis, but the recent Flood<br>of ‘93, that inundated thousands of square miles of land and hundreds of miles of railroad tracks in the midwestem<br>United States, brought a new impetus to quickly locate and repair these hidden subsurface defect areas.<br>This paper illustrates a new technology combination of nondestructive, remote sensing Computer Enhanced<br>Infrared llennography and Ground Penetrating Ruder that was used to detect buried moisture trails and erosion<br>voids of railroad track beds. This technology combination is described in theory and by discussion of a case study<br>based upon a successful project, conducted immediately following the flood, for Burlington Northern Railroad.