摘要: |
The economic constraints of passenger and freight railroad traffic are moving the industry to higher speed rail vehicles and higher axle loads. The dynamics of high-speed trains and the high static loads produce high stresses in the rail components. Track performance under these conditions is strongly related to the vertical track modulus - the relationship between the rail deflection and the vertical applied load. Both low track modulus and large variations in track modulus increase dynamic loading leading to increased maintenance needs and reduced ride quality. Currently, no widely accepted method to measure vertical track modulus from a rail car traveling at significant train speed exists. This report presents a method to measure vertical track modulus from a moving rail car. The method measures the shape of the rail deflection under the moving car and uses a mathematical track model to estimate modulus. The report presents theoretical, simulation, and experimental results. |