Comments on: NCE at 50 | Editors’ key moments: Sydney Lenssen 1972-1976

By: Bill O'Neill

Bill O'Neill — Tue, 14 Feb 2023 22:01:16 +0000

Hi Sid, you haven’t changed a bit – guess you’re still playing squash. Those box girders…they were researching the failures when I was at Imperial in the early 1970s, and still writing stories abt them when I joined NCE in the late 1970s. Enjoyed my time immensely, and relieved to have switched from the worry of designing the next box girder bridge to simply writing about the intrigues of engineering via the great publication that you created …would love to catch up, bill (billoneill@cix.co.uk)

By: Malcolm Frame

Malcolm Frame — Thu, 26 May 2022 11:10:46 +0000

The aspect ratio of box girder bridges was similar to aircraft wings, and ex-aircraft engineers were recruited to re-analyse them and devise strengthening schemes. They had the advantage of knowing how to deal with shear lag. The Merrison guidelines were based on Stephen Timoshenko’s “Theory of Plates and Shells” rendered into a form that could be used directly in a design office. It was said that Timoshenko spent his whole career reproducing his lecture notes from the university of St. Petersburg in the early 1900s.