Analysis of Two way Continuous Bridge under Moving Loads

Abstract

The analysis of dynamic behavior of bridge structures that are subjected to moving loads has been one of the research interests in recent years. Specifically in railway bridges, Resonance occurs when the load frequency is equal to a multiple of natural frequency of the structure. Resonance vibrations have been observed in railway bridges especially subjected to High Speed Lines. They are caused mainly because of two reasons one is the repeated application of axle loads and second is the speed of the train itself. When a bridge is subjected to the moving loads of a high speed train, the dynamic response of the structure is influenced by the soil lying beneath the foundations and surrounding the bridge.

The main objective of this study is to analyze the dynamic response of types of bridges and the underlying soil under traffic. This is achieved by modeling a 3D model of simply supported bridge and analyzing this model for moving loads. The response of the soil medium lying beneath & around the source is observed by Boundary Element Analysis Method. Four types of soil conditions were examined infinitely stiff soil, stiff soil, hard soil and soft soil. The results are shown at the culmination of this work.

Keywords: Dynamic behaviour, High-speed railway bridges, moving loads, Resonance, Tuned mass dampers, Vibration control