Al Bidda Tower

This guide to Al Bidda Tower on the Doha Corniche follows a structural gamble: a forty-three story building that grows wider near its top than at its base, its diagonal curtain wall modeled on a tornado by the Australian firm GHD, built between 2006 and 2009. It traces how engineers wrapped the tower in a steel diagrid, a lattice of angled beams never before tried in Qatar at this scale, where getting the angles wrong anywhere in the spiral could have thrown the loads out of balance.