Effect of Rail Corrugation on the Amount of Train Induced Vibrations near a Historical Building

The evaluation and control of the trains induced vibrations needs even more attention in the case of underground tracks which passes near to monuments and historical sites. The rail corrugations which occur due to the wheels’ impulse loads during the operation period of underground railway tracks, usually amplify the ground borne noise and vibration. In the current study, the mentioned phenomenon is simulated in Isfahan metro line 1 which includes twin tunnels and passes nearby of ChaharBagh School monument. In this matter, a three dimensional vehicle track interaction software (Adams/Rail) was used in conjunction with a geotechnical FEM software (Plaxis 2D). For this purpose, the vehicle-track interaction problem was solved considering rail corrugation in Adams/Rail part of MSC Adams® software and the amplified wheel load was imposed in a 2D plain strain model in Plaxis and consequently, the ground borne vibrations were extracted as vertical vibration velocity at a bench mark points (twin tunnel centerline and vicinity of Char-Bagh School) on the model surface. In this regard, sensitivity analyses were performed on train speed to show the corrugation effect on both increase in wheel dynamic impulse load and root mean square of vibration velocity at a bench mark points. The numerical results indicate that due to presence of rail surface corrugation, axle load increases with raise in train speed. In the worst case, when two trains run simultaneously with 90 Km/hr  in twin tunnels, the maximum induced vibration at bench mark points are about 79.53 and 75.82 dB respectively.