TY - JOUR
A2 - Natsuki, Toshiaki
AU - Zhen, Bin
AU - Luo, Wei
AU - Xu, Jian
PY - 2014
DA - 2014/07/14
TI - Analysis of Critical Velocities for an Infinite Timoshenko Beam Resting on an Elastic Foundation Subjected to a Harmonic Moving Load
SP - 848536
VL - 2014
AB - Critical velocities are investigated for an infinite Timoshenko beam resting on a Winkler-type elastic foundation subjected to a harmonic moving load. The determination of critical velocities ultimately comes down to discrimination of the existence of multiple real roots of an algebraic equation with real coefficients of the 4th degree, which can be solved by employing Descartes sign method and complete discrimination system for polynomials. Numerical calculations for the European high-speed rail show that there are at most four critical velocities for an infinite Timoshenko beam, which is very different from those gained by others. Furthermore, the shear wave velocity must be the critical velocity, but the longitudinal wave velocity is not possible under certain conditions. Further numerical simulations indicate that all critical velocities are limited to be less than the longitudinal wave velocity no matter how large the foundation stiffness is or how high the loading frequency is. Additionally, our study suggests that the maximum value of one group velocity of waves in Timoshenko beam should be one “dangerous” velocity for the moving load in launching process, which has never been referred to in previous work.
SN - 1070-9622
UR - https://doi.org/10.1155/2014/848536
DO - 10.1155/2014/848536
JF - Shock and Vibration
PB - Hindawi Publishing Corporation
KW -
ER -