The Calculation Method for Track Beam on Subgrade Foundation in Low and Medium Speed Maglev Railway Engineering
Research purposes:Low and medium speed maglev railway is a novel transportation system,in which subgrade-track foundation beam structure has significant influences on system safety,operational stability and passenger comfort.In order to establish a simple and rational theoretical basis for practical engineering designs,a calculation method for track beam on subgrade foundation of the maglev railway is established based on the Timoshenko beam model on the Winkler elastic foundation.Research conclusions:(1)The formulas of deflections and internal forces on the beam under vertical vehicle loading are derived after a conversion of the dynamic vehicle load into equivalent inertia force using the pseudo-static approach with considering its boundary conditions,and it is mathematically carried out via the Laplace transformation method.A laboratory model test and on-site testing in a practical engineering are conducted to verify the proposed method.(2)The deflection and bending moment on the track foundation beam both present a parabolic distribution pattern along the beam length with the maximum value at the middle and the minimum at two ends.The maximum relative errors between the proposed and observed deflection and bending moment are about 10%and 5.6%,respectively.(3)The shear force on the beam exhibits a linear distribution along the beam length with zero at the mid-span,and the maximum error between the theoretical and experimental values is approximately 5%.(4)The proposed method can provide reference to specific design for track beam on subgrade foundation in low and medium speed maglev railway engineering.
low and medium speed maglev railwaysubgradetrack foundation beamTimoshenko beammodel test
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