CAUSE AND EFFECTS OF WHEEL LOAD VARIATION ON THE HIGH SPEED OPERATING LINE

Publisher Summary This chapter reviews the cause and effects of wheel load variation on the high-speed operating line. In October, 1964, the Tokaido Shinkansen commenced the operation between Tokyo and Osaka as the first high-speed railway line. In October, 1965, it raised the maximum speed to 210 km/h over the entire line and has since maintained this speed without any fatal problems. In 1969, plans of the Nationwide Shinkansen Network were announced. To test many elements of the rolling stock that would be used on the network, a new test train called 951-type was constructed. Various tests had been conducted mainly on the Tokaido Shinkansen with this train until 1972. In the tests, the attention of researchers and engineers in Japan National Railways (JNR) was attracted to the fact that there were much greater wheel load variations in the test train than in the operating trains. A rapid increase of wheel loads with the train speed that occurred in the test using the 951-type test car on the Tokaido Shinkansen revealed that the control of the sprung and unsprang weights of car, the control of the track spring constant and the damping constant of track spring, the control of the rail surface, and the control of the deterioration of ballast were essential to realization of operation of high speed commercial trains.