My first two features* comparing CP3 and BS 6399: Part 2 covered the rules on ground roughness and the modification of the ‘division by parts’ rule. In this feature I cover the remaining aspects of the design wind speed rules - the climate-dependent parameters. This is the only component of the wind Codes that applies solely to the UK. I then compare the design wind speed and dynamic pressure predicted by both Codes for various sites across the UK, demonstrate how best to eliminate unwanted conservatism, and introduce the design aids available for the parts of the Code covered so far. N.J. Cook
Dr B. R. Ellis (M) (BRE) I have been involved with structural dynamics for many years and also with measurements on many grandstands -hence I was very interested in this paper. There were a number of items in the paper which surprised me, in particular its links with the March 1997 version of the ‘Green Guide’. The guide introduced a new regulation which is: ‘Dynamic load effects may be caused by (a) Excitation by wind. (b) Excitation by activities of spectators. Where a seating deck has a vertical frequency less than 6Hz or a sway frequency less than 3 Hz, a dynamic evaluation of the structure should be carried out giving due consideration to the mass of the spectators. (c) Excitation by the activities of the spectators at grounds staging pop concerts or other events involving rhythmic activity, in which case the design loads may be even greater than for category (b)'
Six full-scale tests on reinforced concrete flat-slab to edge-column connections are described. The strength of the specimens compared well with predictions based on BS 8110. Nevertheless, it is suggested that the shear stresses within the joint region of the column should also be considered. D.E. Parker and P.J.M. Bullman
The combination of a radical idea, mass manufacturing techniques and close design collaboration have resulted in the speedy construction of a new underground recycling facility at Ford’s Bridgend plant. M. Swan, G. Wright and D. Rowbottom