A technical hitch resulted in the omission of the authors' names from the article 'Impressing the current in Birmingham' (CONCRETE, April 2004, pp.35-36). The authors were Peter Robery and Kate Turnpenny of FaberMaunsell and we apologise to them for this error.
The Beco Wallform advertisement
Unfortunately Figure 2 of the article The future specification of cement type, class and water/cement ratio. Part 2: Durability considerations for cements containing approved secondary main constituents and additions' published in CONCRETE, March 2004, p.48 is missing the key. Here is the correct version and we apologise to John Newman and Philip Owens, the authors.
IMAGE GRAPH 1Variation of ratio of core strength to 28-day cube strength with age of coring.