Form finding of the Tower bridge

The design of the Tower bridge is based on the superposition of the funicular lines for two load cases, the self-weight of the bridge and extreme asymmetric load cases, represented by an additional uniformly distributed load on either part of the span respectively. All funicular lines pass through the 3 points, the result is the enveloping surface of all possible funicular lines.

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Use the slider to go through the steps of the form finding process: 1-3) constructing the funicular line for the uniformly distributed load through 3 points; 4-6) constructing the funicular line for an additional uniformly distributed load for either part of the span; 7) constructing a moving point load; 8-9) integrating the two loadlines into a combined loadline to construct the funicular line for the combined load case.
Use the slider to move the point load along the span of the bridge. Use the sliders to vary the relation between the different load cases. Note that the found funicular line is always contained within the geometry of the bridge.