Special Study Groups

At the open meeting of the Institution held on 8 January 1970 (see p. 3 of The Structural Engineer, January 1970, Mr. A. J. Leggatt, presenting the above graph, said: ‘I have concocted a graph (Fig Dl) which is, at the least, controversial; and if it is so controversial that people laugh at it then I will escape under your clause of light-heartedness. I have plotted “claim” as a percentage of the contract sum. Profit is also expressed as a percentage and I qualify that as “tender profit”-that is the profit that the contractor hopes and aims to make at the time of tender. I think the contractors will giggle at the maximum of 25 per cent, but you can put your own values for this graph and the principles remain the same. I have also introduced a new parameter “Ti” which gives it a scientific appearance. “Ti” is the “tightness” of the contract.‘

Dr. R. E. Rowe: ‘It is in a certain sense with some diffidence that I open the discussion since basically I agree whole-heartedly with what Dr. Flint has been presenting to you this evening. However I would like to raise a number of general points and then discuss them. ‘Firstly, from the general point of view I think we must all welcome the paper as it deals with the application of limit state principles to the design of bridges. The authors have taken what are conventional design practices for bridges as they stand at the present moment, and analysed them in a fairly comprehensive way giving us an enormous list of factors and showing what we are doing at the present time. The authors referred in one part to the work of one of the road research panels-Panel S-dealing with load factors and I would merely like to quote some figures coming from that source to endorse what the authors have said particularly with regard to composite slab bridges.'

Dr. Allwood: ‘I am delighted to have this opportunity of opening the discussion after Mr. Alcock’s excellent presentation. This gives me an opportunity to explain to you something of the Genesys Centre and its position relating to the development of the system.'