Chris Warrell, Tim Surtell and I went to the RIBA Family Fun Day on 2nd April 2016. The participants built bridges.
For a bit of fun Godzilla occasionally went around looking at the bridges and would go up to the Godzilla bridge and bend it out of shape. The bolts in the middle of the bridge are held in place by anchoring springs with lock nuts at the end. Since they are in slotted holes they an move about in the holes and hence the bridge can be deformed.
It went down well. Tim’s device for testing bridge fail weight won the day for me.