1 Post Graduate Student, Department of Earthquake Engineering, Indian Institute of Technology, Roorkee, Uttarakhand, India
2 Assistant Professor, Department of Earthquake Engineering, Indian Institute of Technology, Roorkee, Uttarakhand, India
The joints of Riveted Steel Truss Railway Bridge consist of gusset plates which lose their rigidity due to repeated passages of train loads; therefore the loss of rotational rigidity is to be taken into account in analysis of Bridge. This joint flexibility tends to alter the vibration characteristics of the Bridge system and each component of the bridge responds dynamically to the rapidly varying loads and thus the time history obtained is a function of load variation and dynamics of the structure, which consequently affects fatigue life of the bridge components. In past, effect of Semirigid joints has been studied in case of building frames. So here the knowledge of semirigid joints on building frame has been extended to Steel Truss Railway Bridge. This present article tries to study the influence of joint flexibility on the fatigue life of 76.2 m Truss bridge due to moving load at different speeds. The joint rotational stiffness are reduced by 5%, 10%, 25% and 50%. The result of preliminary studies conducted on Steel Truss Bridge is presented. It is prime facia that upto 50% reduction in rotational Stiffness of the joints does not affect the stability of the bridge. However more detailed studies are required to confirm the findings.
Riveted steel bridge, Railway bridge, Bridge analysis
