Dynamic Simulation of Freight Car and Lading During Impact

Abstract

A dynamic analysis is presented to explain damage to railroad cars and ladings resulting from impacts. In the analysis, a mathematical model consisting of the car body and freight in the car is presented. Each freight element assumes three degrees of freedom for the computer simulation. A parametric study is made to establish sensitivity of car parameters and impact conditions. The study should be useful to aid in finding means for controlling impact damage and in designing packaging materials.

Advanced dynamic modelling for friction draft gears

“…These parameters play specific roles in this model: h 1 represents the kinetic friction; the sum of h 1 friction to kinetic friction. The exponential model was selected not only just for its popularity [21] but also based on experimental evidence that suggests that it can achieve a good fit for the dry friction in friction draft gears.…”

“…Field tests on Datong-Qinhuangdao Railway, China [8] have recorded cases of abrupt in-train forces and locomotive lateral instabilities caused by locking and sudden unlocking of friction draft gears. The adverse draft gear performance of 1 Follower, 2 Central wedge, 3 Wedge shoe, 4 Release spring, 5 Outer stationary plate, 6 Movable plate, 7 Lubricating metal, 8 Inner stationary plate, 9 Spring seat, 10 Main springs and 11 Housing.…”

“…During shunting operations, draft gears are probably the most important devices to protect rolling stock systems; inappropriate draft gear behaviour or inadequate dynamic performance could result in component failure or/and goods damage. [1][2][3] Theoretical studies [4][5][6] have shown that, during normal main-line operations, the dynamic behaviour of draft gears has implications not only for longitudinal train dynamics but also for rolling stock fatigue. Note that reference [4] was about the pre-load of hydraulic end-of-car cushioning devices, but the implications also apply to friction draft gears.…”

A review of dynamics modelling of friction draft gear

“…The T&S approach was reported by Martin and Hay [17] before the TTD project (Martin was a member of the Steering Committee for the TTD project); this approach is also widely used in other publications. [18][19][20] In 1986, the Association of American Railroads (AAR) developed the Train Operation and Energy Simulator (TOES) as a successor to the TOS. [21] TOES was developed under the auspices of the Vehicle Track System (VTS) research project, a successor to the TTD project.…”