Better Construction Through the Potential of Timber I-Beams

Shear in concrete Ian Feltham writes from London, W1: Although we all prefer guidance that results in greater structural economy, Arup Research & Development is advising users of BS 8110 within OAP of two instances where the Code permits shear designs with a lower factor of safety than other Codes and where a more conservative approach should be considered.

The West Stow Anglo-Saxon Village is a cooperation between St Edmundsbury Borough Council, the West Stow Anglo-Saxon Village Trust, and the Friends of West Stow Anglo- Saxon Settlement. The chance finding of fragments of pottery unearthed by burrowing rabbits led to the discovery of this important archaeological site. Fortunately, the area had been covered by a sand dune since the 13th century, giving archaeologists the opportunity to study a largely undisturbed Anglo-Saxon village. Most of the original timbers had decayed, but Suffcient evidence remained to plot the changes that took place between the 5th and 7th centuries and to gain a good impression of the form of the settlement. To make the discoveries accessible to the public, the village was reconstructed using tools and techniques available to the Anglo-Saxons. Fig 1 gives an indication of these reconstructions, each of which tests specific archaeological ideas. Deb Turnbull and Martin Milner

The ‘double entry-point’ to design caused by timber remaining ‘working stress’, whilst other materials have long been ‘limit states’, is no longer helpful to professional engineers. To overcome the problem, TRADA Technology, with funding from DETR and TRADA, is undertaking a project entitled ‘Demystifying limit states design in timber’. The project has an Advisory Group, chaired by consulting engineer Stefan Tietz, and includes other practising engineers, timber design specialists, TRADA engineering staff, and an educational representative from the University of Bath. Professionally, the project involves the Institution of Structural Engineers’ regional branches and the Professional Activities Group. The UK Glued Laminated Timber Association (GLTA) is also contributing. Christopher Mettem and Stefan Tietz