Sir, I owe an apology for the undue compression of my letter on- the above subject in the July issue of the STRUCTURAL ENGINEER. The reason was that I was uncertain whether the point was novel or not. It seems from Mr. Cornish’s letter in the current issue-for which I am obliged-that it is novel. I would therefore like to set out the argument in more detail, taking a rather different line of approach.
It can be said that structural steelwork is the same whether produced for normal uses or for railway work, but railway work presents very definite problems and difficulties which I hope this paper will show. J.S. Campbell
REINFORCED concrete structures are in many cases so redundant that a complete mathematical design is impossible and certain assumptions are made to simplify procedure. W.T. Marshall