This paper outlines the methodology used to construct, first, the stiffness matrix needed for a static distribution analysis of a road over rail bridge and second, the dynamic stiffness matrix and procedure required for the calculation of the lowest natural frequency for a single span footbridge using only a Microsoft Excel spreadsheet.
Exceptionally tall or slender columns may necessitate finite element modelling to determine the effects of buckling. However, in many cases an accurate assessment of the critical buckling load can be made by hand calculations incorporating spring supports or tapered/stepped stiffness columns. This paper discusses the calculation of the buckling load for the end conditions given in Eurocode 2, including various rotational spring restraints and variable stiffness within the length of the strut.
This paper simplifies the analysis of the dynamic response of structures to a sinusoidal loading to provide arithmetic solutions and a means of understanding the dynamic response of a structure. It also provides a means to estimate the characteristics (mass, stiffness and damping) of a TMD to address any residual problematic dynamic response. This enables the design provision for the additional weight attached to the structure and the required space, if a TMD is deemed to be necessary. A worked example of a simply supported welded steel box girder footbridge is presented.
This paper presents a solution to undesirable acceleration effects experienced by pedestrians on the Eagles Meadow Footbridge in Wrexham. The installation of a tuned mass damper reduced the vertical movement of the bridge to near imperceptible levels. An analysis by hand calculation of the bridge dynamics and tuned mass damper characteristics is presented.