The Twin Cable-Stayed Houston Ship Channel Bridge

Engineering Council subscriptions Allan Love, from Eastbourne, has written: Engineers are generally logical, sensible people who, if they see conflicting ideas, will try to resolve things to a point where things ‘look right’! Which is why I am trying to see any logic in being able to call myself a ‘Chartered Structural Engineer’ (MIStructE) but, if I have not paid my Engineering Council (EC) fee of £22, I may not call myself ‘Chartered Engineer’ or CEng.

An unusual landscaped bridge, now under construction, will provide a crucial element in the comprehensive programme of regeneration and extension for Mile End Park in London’s East End. The scheme’s masterplan, conceived and designed by Tibbalds Monro, will create a 5-mile linear park by linking a series of open spaces currently dissected by major arterial roads and railways. Michael Patrick

In order to control the alignment and stresses of the Flintshire Bridge, accurate long-term creep and shrinkage data were required for analysis by a finite element model. Since the concrete contained mineral and chemical admixtures, the design model of BS 5400: Part 4 was deemed to be inappropriate, as the creep and shrinkage factors apply for admixture-free concrete. Consequently, laboratory tests were undertaken in which specimens were loaded at ages corresponding to the prestressing and tensioning operations of the bridge segments. Elasticity, creep and shrinkage were measured over a period of 1 year and compared with values estimated by five methods of prediction. The methods were then used to extrapolate the l-year laboratory results to equivalent 50-year deformations of the bridge segment and to estimate the halffinal deformation times and the eflects of a change in mix proportions on creep and shrinkage. J.J. Brooke and H. Al-Qarra