You know those huge electrical transmission towers?

(c) Bidgee, Wikipedia

I did a study about their structural design for my master's thesis. Anyways, there was this contest in the UK for the best modern replacement shape for the almost-one-century-old tapered steel lattice/truss form. There were plenty of submissions, most of them very interesting. The first concern I had in mind, having my structural engineer's goggles on, is that it has to be very efficient structurally, meaning it should use the least amount of material possible and yet it has satisfactory strength to withstand the elements and nature, along with its high uncertainties.

I thought that the current, now classic structural form it uses - a tapering steel truss/lattice tower - is the most efficient and nothing can replace it. Put any larger elements in there, or add some eccentricities to become more artsy and what not, and you are bound to increase the structural demands, and hence, the size and cost. Image number 5 of the 10 shown in "Pylons of the future?, a BBC News image gallery" was the first to catch my attention because it appeared to have some sort of post-tensioning - a structural feature - which allows it to become stronger even with relatively very slender elements. Surprisingly, engineers behind the design were Arup, a company that is quite familiar to me. I definitely had the tendency to ignore those other "aesthetically pleasing architectural designs" that did not have sufficient engineering thought put into it.


P.S. Thanks to Mela for the link.