ON THE MEASURING METHOD OF THE CREEP FORCE BETWEEN WHEEL AND RAIL

When a wheel runs on a rail, there occurs a small slip at the contact surface between wheel and rail. When slip is very small the tangential force is in proportion to the slip. The proportional constant is so called creep coefficient. An experiment to measure the creep coefficient was carried out with one-fifth scale model. As the results, the following facts were obtained: 1. The value of creep coefficient increases in proportion to the wheel load to the two-thirds power, that value is nearly close to F = 1/pi x area of ellips x Young's modulas. 2. The longitudinal creep coefficient is larger than the lateral one. 3. As slip increases, non-linear characteristics appear. 4. The value of creep coefficient is in inverse proportion to the displacement of wheelset, that is, as the displacement becomes large, the value of creep coefficient becomes small.