Millennium Man
This highly unusual structure was created by Antony Gormley for a site on the Thames outside the Millennium Dome. Another of his famous sculptures is the Angel of the North, near Gateshead. The essence of the structure is that it is a mass of branches in steel which, by virtue of the varying density of these branches, reveals the shape of a man within. This posed some interesting problems for the engineers tasked with helping to make the sculpture a reality.
The approach was to divide the sculpture into slices, determine their solidity and to treat the loading as if it were a series of lattice frames. The shelter afforded to the downwind lattices was then accounted for to ensure that the resulting load was not unnecessarily conservative. A second issue that arose was the possibility of dynamic excitation leading to fatigue damage. The branches are cantilevered out from the central region and are mostly triangulated for rigidity. However, this is not true of the outer ends and tests on a model version of the sculpture suggested that the natural frequencies were in a range of concern. The key unknown, as in many dynamic analyses, was the degree of damping.
