Triennial Report 2003 - CHARMEC

Interaction of train and track – Samverkan tåg/spår (TS) – Wechselwirkung von Zug und Gleis – Interaction entre le train et la voieTS4. LATERAL TRACK DYNAMICSLateraldynamik och korrugeringLateraldynamik der GleiskonstruktionenDynamique latérale de voies ferréesProject leaderand supervisorAssistant supervisorProfessorThomas Abrahamsson,Applied MechanicsDocent Jens Nielsen,Applied MechanicsDoctoral candidate Mr Clas Andersson(from 1997-01-01;Lic Eng November 2000;PhD June 2003)Period 1998-01-01 – 2003-02-28Chalmers budget Stage 2: ksek 2000(excluding university Stage 3: ksek 1300basic resources)Industrial interests Stage 2: ksek 700in-kind budget Stage 3: ksek 200(Banverket)Railhead corrugation leads to wear, vibration and noise,and the maintenance grinding of rails involves substantialcosts. The mechanisms for the origin of railhead corruga-tion are related to concurrent vertical, lateral and longitudinalinteraction between train and track in the wheel/rail interface. In the ts4 project, the diff calculationmodel (see under project ts1) has been extended toserve as a tool for the analysis of this three-dimensionalinteraction in the frequency range up to about 1500 Hz.Like diff, the new computer program works in the timedomain and it has been called diff3d. The model ofthe vehicle in diff3d permits large rigid body movements(important to running dynamics) simultaneouslywith small elastic deformations of the components. Thecoupling to the track includes wheel/rail contact zonedetection. Both elasticity and creep in the contact zoneare considered. A suitable fe model of a bogie wheelsethas been established. Finite elements have been used tomodel both the running surface of the rail and the railas a whole. Both tangent and curved track can be investigatedby use of diff3d.The experimental basis of the track model has beendeveloped in full-scale measurements in co-operationwith Banverket at Grundbro on a stretch of tangent trackof the Svealand line. Direct and cross accelerances forrails in vertical and lateral directions were registered.Photo: Lennart Lundfeldt, BanverketDr Clas Andersson (right) and Professor Thomas Abrahamssonof project TS4Short pitch corrugation at Kilsmo on the Western Main Linein Sweden16