Victor V. Krylov
Ctr. for Res. into the Built Environment, Nottingham Trent Univ., Burton St., Nottingham NG1 4BU, UK
The dramatic revival of railways in Europe to become one of the most advanced and fast developing branches of transportation technology may be compared with the space technology breakthrough of the 1960s. The reason is high speeds achievable by the most advanced modern railway trains, e.g., French TGV trains for which a maximum speed of more than 515 km/h was recorded in May 1990. Unfortunately, the increased speed of railway communications is likely to raise levels of associated environmental noise and vibration far beyond those significant even for conventional railways. A review is given of recent progress in the theoretical investigation of ground vibrations generated by high-speed railway traffic, with emphasis on problems associated with superfast trains, i.e., trains traveling at speeds close to or greater than 300 km/h. Significant increase in ground vibration levels (more than 70 dB) is predicted for superfast trains if they travel at speeds higher than Rayleigh wave velocity in the ground [V. V. Krylov, J. Phys. IV, C5 4, 769--772 (1994)]. Attention is paid to establishing relations between parameters of the problem, e.g., geometrical dimensions of track and train, layered structure of the ground, train speed, etc., that could result in direct reduction in ground vibration generation efficiency.