| Conventional jointed rail track has an inherent weakness that the rail-working surface is broken at rail joints. Most track deterioration occurs at these joints. The use of continuous welded rail (CWR) track reduces the cost of track maintenance and increases the life cycle of track components significantly. Extreme temperature stress can, however, cause CWR track to buckle (lose stability) in the summer and pull apart in the winter. In 1995, the Association of American Railroads (AAR) estimated the cost of derailments caused by track buckling as approximately {dollar}25 million annually.; The focus of this research was to develop a three-dimensional (3-D) CWR track model, ILLIBUCKLE. The model was used to analyze the stability and lateral shift of tangent and curved track subjected to mechanical and/or temperature loads using the finite element method (FEM). The maximum CWR track length in this model can be up to 5000 or 6000 m, depending on tie spacing and available space in the computer.; Existing field test data and theoretical analytical results were applied to validate the model. The model indicated that track buckling is a 3-D problem and those 2-D models and previous field/laboratory track buckling tests overestimated CWR track stability. Track-buckling temperatures measured in the field and laboratory tests have meaning only when corresponding to specific end stiffness of CWRs even if the track reaches several hundred meters (200 m or 650 ft) in length. The influences of many CWR track parameters can be investigated in ILLIBUCKLE, including the following: track gauge; track geometrical imperfection; neutral temperature difference in two rails; ballast lateral, longitudinal, and vertical resistance; fastener stiffness; rail-joint resistance; reduction of ballast resistance in a few ties due to tamping or uplift of the rail bending wave under vehicle loads; and missing fasteners in a few ties within one and/or two rails.; Innovative methods of enhancing the stability of tamped track and sharp curved track are recommended according to the theoretical findings from this research. Using the innovative methods, railroads can eliminate or reduce slow orders following tamping or track surfacing to improve railroad productivity. |
