Issue 8

Mr. D.R.R. Dick (F) (Past-President) : I think the authors are to be congratulated on their very interesting paper, particularly those parts where they relate their practical experience to future actions.

Professor N. Simons: Being a foundation engineer I obviously found a great deal of interest in the paper. but I would like to discuss one point in particular this evening and this is this philosophy of the design of a piled raft about which the authors have written. Considering raft foundations in the London clay, which are also piled, in many cases the piles are provided solely to reduce settlement. In other words, if there were no piles whatsoever, there would be a perfectly adequate factor of safety against failure. So when such piles are installed only to reduce settlement then obviously the design concept must be considered. The point I wish to make is; should the piles be designed to carry the total building weight, or is it necessary only to carry the net increase in loading on the piles?

Mr. C. W. Brown (M), Freeman Fox & Partners: The phenomenon of shear lag is one that until recently has been at best imperfectly understood. Manual methods of estimating its effect were very complicated to apply and were applicable only to highly idealised cross sections and loading conditions. Certain simplified empirical rules were proposed in some Codes, but the authors' paper describes the first real attempt to provide comprenehsive but comparatively simple rules. This, of course, has only been made possible by the availability of powerful finite element computer programs, and the authors deserve great credit for their presentation of a vast amount of information in four straightforward Tables (7(a) to (d)).

COUNCIL l976/77 Brief biographical notes of the recently elected Honorary Officers, London and Country Fellows and Members who will be serving on the Council for 1976/77 appear on page 284.

This technical note deals with properties of chains of equilateral spherical triangles constructed on the surface of a sphere. The properties discussed in the paper seem not to have been noticed by any one before. The division of a sphere into icosihedral and tetrahedral divisions are shown to be only particular cases of these chains of equilateral spherical triangles. Structural engineers can make use of these properties to divide spherical and cylindrical surfaces into reasonably small areas with identical arcs (or chords) and hence construct braced domes and vaults with identical members. K.S. Rangasami and S.M.R. Kaburu

The present statutory control of building and engineering works in the United Kingdom varies greatly in terms of quality and efficiency. There are separate systems, for England and Wales, for Scotland, for Northern Ireland, and for the inner London area. The system proposed in this report will provide an integrated control structure independent of central or local government and therefore more readily adaptable to suit future changing needs.

Possibly, because it is under revision, we have not had many comments in the past on BS449. However, a reference to the forthcoming revision in the paper by Johnson and Smith (September 1975) has drawn the following from Mr. R. Taylor: It is interesting to note that in their paper concerning deflections of composite beams, Johnson and Smith, quoting from the forthcoming revised BS449, state that the final deflection of a beam below the level of supports should not exceed span/250, or for a cantilever length/l25. Since this particular limitation is from the appearance standpoint, the relative values quoted for a beam supported at each end and for a cantilever seem logical. Verulam