S. B. Desai (M): It can be observed from the formulae given in the paper (as well as clause A.3.2 of CP 110) that the calculated crack widths in RC members are proportional to the covers provided to the reinforcing bars. Because of this, the design of structures exposed to severe conditions (e.g. a marine environment) seems to have to satisfy somewhat over-stringent criteria.
Professor B. P. Hughes (F) (University of Birmingham): I should like to congratulate the author on a most interesting and useful paper, and for his presentation of the theoretical background to the crack width predictions given in the current British Codes of Practice. Dr. Beeby has asked, ‘Is the picture reasonable and right, and what limitations has it?’
President’s diary Following his installation on Thursday 2 October, the President 1980-81, Professor Michael Horne, with Mrs. Horne, will visit the Scottish Branch on Monday and Tuesday, 6-7 October. Professor Horne will attend the Branch Inaugural Meeting for the new Session on the Monday evening and, with Mrs. Horne, looks forward to meeting members, their ladies, and guests at the Branch Annual Dinner and Dance the following night.
The optimum design of a range of steel roof structures is established using a combination of non-linear programming methods. The objective function is cost orientated and a suitable cost model is described. The relative costs of seven types of roof structure are compared and conclusions drawn as to cost effectiveness. A.B. Crawford and W. M. Jenkins
The subject of this paper is the field erection of the off gas stack at Chin Shan nuclear power station, Taiwan. This is a braced frame structure composed of tubular members. The leg splices were site welded and all other connections bolted. A.P. Mann
The computer debate From Mr M. K. Hurst his views on the use of computers: I have been following with interest the debate on computers which has been continuing in the Verulam columns, and I would like to add my two-pennyworth. It seems to me that computers have two distinct advantages over the human brain-their ability both to store and retrieve vast quantities of information and to perform lengthy calculations on them, both operations being performed extremely rapidly and accurately. As long as computers are used to perform just these functions, as is the case in most business applications, they are being used to their best advantage. Verulam