Transportation Vehicle/Beam-Elevated Guideway Dynamic Interactions: A State-of-the-Art Review

The importance of elevated guideway/vehicle dynamics to the design of advanced ground transportation systems is discussed and the general vehicle-suspension-guideway interaction problem is outlined. Simplifying assumptions valid for many practical beam-type elevated guideway systems are described including the Bernoulli-Euler beam assumptions, support conditions, and simplified vehicle models. The theoretical and experimental literature on beam-guideway/vehicle dynamics is reviewed and recent computer-based analytical techniques (lumped mass, finite difference and modal analysis) are discussed. Available simulation programs are described and published results for wheeled, air cushion and magnetically levitated vehicles operating over beam-elevated guideways are reviewed. The influences of critical system parameters on guideway deflection and vehicle vibrational acceleration (ride comfort) are illustrated through simple limiting case analyses. Low ratios of vehicle-suspension to guideway natural frequency and distribution of vehicle weight over finite pressure pads as in air or magnetic suspensions reduce guideway structural requirements for specified ride comfort. Continuous guideway beams on simple supports provide lower static deflection and greater dynamic range than simply supported single or multiple span beams. Severe resonance problems which may occur in synchronous vehicle systems are illustrated using a point-force vehicle model.