Continuous Construction in Steel for Roofs and Composite Floors

Bending moments in brickwork panels Mr A. Aiken's letter, published in July, has prompted several replies. Mr J. E. Saul writes to us from Mold, Clwyd: Mr Aiken's problem is that he has not realised that brick panel design in BS5628: Part l is based on plastic principles. Well mostly, that is panel analysis is, but section analysis is not that is elastic. Anyone could be excused for making this mistake since, apart from being confusing, it is also well wrapped up by the Code writers. Verulam

The paper proposes some rules for selecting bed-joint reinforcement in brick facade walls which may be susceptible to settlement. Loading criteria are adopted in preference to deformation criteria, and the importance of specifying a minimum amount of reinforcement and of the need to provide ductility is emphasised. The use of the equations is demonstrated on a four-storey wall. Professor I.A. MacLeod

Mr Liddell: There was really only one suitable fabric for the roses - teflon-coated glass fabric cloth-but, for a variety of reasons, alternatives were considered during the design stages, the main reason being that Frei Otto distrusted the material because of a disastrous experience at Cologne in 1957 with glass fibre cloth coated with PVC. Glass fibres do not degrade in sunlight in the way that organic fibres do, but they are weakened by water and are brittle and hence can suffer mechanical damage.