Since graduating in 1966 I’ve never worked as a consulting engineer, or as a contractor, or as an academic, although these groups of civil and structural engineering graduates probably account for more than 90% of the people in our profession. Dr Kieth J. Eaton
This paper concentrates on the parametric stress analysis of steel, multiplanar tubular XT-joints using the finite element (FE) method. An extensive database of stress concentration factors (SCFs) at fixed hotspot stress locations was built by carrying out about 600 runs of FE analysis on 84 XT-joint models covering a wide range of geometrical parameters. Nine different load cases of basic brace and chord axial, in-plane-bending (IPB) and out-of-plane-bending (OPB) moments were considered Through parametric study, a new set of SCF design equations were established for general end load conditions. The new definition of the hotspot stress (HSS) from the latest research findings was adopted. This allowed the use of the superposition method of these equations to predict the HSS of multiplanar tubular XT-joints under any arbitrary combinations of brace and chord end loads. In addition, an assessment of these parametric equations was carried out using the latest acceptance criteria from the UK Department of Energy (DOE), and the study confirmed the accuracy and reliability of the proposed equations. S.P. Chiew, C.K. Soh and N.W. Wu
A former china claypit at Bodleva, near St Austell in Cornwall, is being transformed into a 21st century ‘garden of Eden’ with an unusual and innovative structure. Two huge bubble-like domes (biomes), composed of steel spaceframes covered with triple layers of ETFE (Ethyltetrafluorethylene), have been constructed in the 60m-deep crater to form the world‘s largest greenhouse. It will become a protected environment for plants from around the world in settings which explain their habitats, uses and environmental importance to visitors. Kathy Stansfield
The paper covers the provision of two safety-related steel caissons to replace existing caissons (sliding steel gates) for the Ministry of Defence at Rosyth Royal Dockyard. It briefly describes the existing caissons, to set a framework for the stringent limitations imposed on the new caissons, and addresses the brief, procurement and safety case approval requirements. The design had to take into account the effects of all potential environmental hazards, and the paper covers the complexities of the seismic analysis, together with the other significant and often unique design issues that had to be overcome. G. Forsyth and A. Porteous
For some time the tubular column has been a staple of the construction industry. However, in its form as a concrete-filled tubular steel composite column, it now has attributes of speed and efficiency which can give it important advantages in multi-storey construction. Andrew Orton
Torsion in Steel Beams This has raised further comment. Bing Choy writes: I’m a user of BS 449 as my design code but face a problem in dealing with the estimation of the effective length that is required to calculate the permissible compressive strength that makes the beam not suffer from buckling.