Vibration of a suspension bridge installed with a water pipeline and subjected to moving trains

Abstract

This paper presents a first study on the vibration of a suspension bridge installed with a water pipeline and subjected to moving trains. The suspension bridge is modeled as a single-span beam suspended by the hangers and hinged at the two ends. The train is simulated as a sequence of equidistant moving loads with identical weights. The liquid flowing through the pipeline is simulated as a strip of continuous mass moving at constant speeds. The governing equation is transformed into the generalized coordinates by Galerkin’s method, and solved by a rigorous incremental–iterative procedure that takes into account all the nonlinear effects. The results indicate that the critical position for the maximum acceleration of the suspended beam to occur under the moving loads depends upon the modal shape that has been excited, which can be antisymmetric or symmetric. The inertial effect of the flowing mass is beneficial for mitigating the vehicle-induced acceleration of the suspended beam, if the flowing speed is kept below the first resonant speed of the moving loads.