The acerbic content of the letter from Alan Rees on Bill Brown (NCE 5 June) requires a response.
I joined Freeman Fox immediately prior to the Yarra Bridge collapse and one of my first jobs was to work for Oleg Kerensky on a design check on the Erskine Bridge which was under construction at that time.
I then spent many weeks in the next 12 months checking the integrity of bridges against the various versions of the "Merrison Rules" which were to be finalised in the design rules that were in the Appendix to the Merrison report.
I would recommend the papers presented at the International Conference at the ICE on 13-14 Feb 1973 on "Steel box girder bridges" be read. The opening address and introduction by Dr Merrison highlight that the two collapses referred to by Mr Rees were preceded by a bridge collapse across the Danube, and in November 1971 the Koblenz bridge collapse killed 12 men.
This was not a UK problem alone, let alone a "Bill Brown" problem. Of the 81 bridges checked in England against these new design rules, 69 required strengthening.
With regard to the Yarra Bridge collapse I quote from Dr Merrison's introduction: "The lessons for the designer here – though not absent – were slight compared with the lessons for human beings in general..."
Progress requires people with imagination; and for us all to benefit from the lessons that can be learned along the way.
DAVID A WALKER (M), 8 Berisay Place, Stornoway, Isle of Lewis HS1 2TF