Discussion on Developments in the Design of Bouyant Ferry Ramps

Dr. K. Fisher (Chief Technical Officer, Redland Brick): Mention was made in the paper of model testing of diaphragm walls, an aspect given further mention in the accompanying paper. I should like to comment briefly on the axial loading tests which we carried out at Redland on model diaphragm walls. (The results have been fully detailed in a paper given to the 5th International Brick Masonry Conference held in Washington at the end of 1979.)

Dance halls A collapse this year in America has highlighted the problem of rhythmic loading on the floors of dance halls, and we have received the following letter from Mr W. G. Scott (of Lothian Regional Council) who was involved in some of the problems at Edinburgh Playhouse. Verulam

A number of inconsistencies in the approaches given in British Codes for the design of reinforced concrete slabs are discussed. These are cases where a more rigorous design leads to a requirement for more reinforcement than do simplified methods. Since experience suggests that the simplified methods are adequate, a review of the bases of slab design seems necessary. Various aspects of the behaviour of slab systems are discussed including the nature of loading and membraneffects. It is suggested that the more rigorous design methods are indeed overconservative, and a change in the design load patterns is proposed. A.W. Beeby