Study on Determining the Design Value of Lateral Swaying Force for High-speed Railway Bridges Based on the Responses of the Bridge
Research purposes:The lateral sway force of trains is a crucial factor influencing the lateral stiffness design of bridge structures.However,current design practices often inadequately consider the dynamic effects of lateral sway forces.This paper employs a coupled simulation analysis method for train-bridge interaction to investigate the impacts of train speed,bridge span,and pier height on lateral dynamic response.By integrating the theory of moving load passage over bridges,the relationship between the lateral fundamental frequency of bridges and lateral dynamic response is examined,elucidating the conditions for lateral resonance in bridges.Adhering to the principle that operational live load effects should not exceed design live load effects,an approach is proposed to comprehensively account for the dynamic effects of lateral sway forces by designing the lateral sway force multiplied by the lateral dynamic amplification factor.Research conclusions:(1)Within a specific velocity range,the lateral dynamic response of bridge structures exceeds the static response calculated based on the designed lateral sway force,revealing a tendency towards insecurity in the current assessment of lateral sway force values.(2)There is no significant correlation between the lateral dynamic response and the span of simply supported beams.However,the influence of pier height is more pronounced.The velocity range where lateral dynamic peaks occur diminishes with increasing pier height.(3)For simply supported beams with lateral fundamental frequencies within the range of 3.5 to 5 Hz,a lateral dynamic amplification factor of 1.44 can be applied.In other frequency ranges,the correction for dynamic amplification factor may be disregarded.(4)This study can serve as a reference for determining lateral sway force values in the design of high-speed train systems.
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维普
