Detection of underway gaps in rail systems by simulative and experimental methods

In this study, simulation and experimental studies have been carried out to determine the gaps formed under the rail line in rail transportation. In the simulations, where the analyzes are carried out with the finite element method, two different rail line conditions are designed for the normal and the defective lines. The displacement amounts and acceleration data in the vertical axis are examined for the normal and defective line conditions of the obtained vibration effect. The experimental conditions were designed in exact harmony with the simulative environment. A vehicle was moved at a constant speed of 0.112 m/s that has 1666 kg mass during the experiments. Vibration effects on the ground were monitored instantly with the acceleration sensor placed on the vehicle. In total, 4.425x10(-3) m(2) defected area is created under the certain points of rails. After the smooth and imperfect paths were examined both experimentally and simulatively, the results were presented comparatively in graphs. Although the gap is small, the difference between the normal and defective line reaches 61.8% for the displacement data in the simulation. In addition, 108.7% and 12.5% changes occurred, respectively when the simulation and experimental acceleration data were examined between faulty and the normal line. Eventually, the proposed method became a candidate to offer solutions for detecting underway gaps along the line.