Correspondence on Temperature Distributions and Stresses in Concrete Bridges by E.C. Hambly

Mr. T. A. G. Raikes (M) (Ove Arup Resident Engineer): We thought it would be useful to start the discussion by saying something of how the diaphragm wall construction worked out in practice, particularly in relation to the use of T-shaped and Ushaped panels.

Local authority responsibility A structural engineer employed by a local authority once again raises the issue of where the responsibility should lie if structural defects arise in a building. He writes: I am concerned athe almost standard procedure which now seems to be accepted in respect of the submission of structural designs and calculations for Building Regulations approvals. It seems to me most unfortunate, and certainly not in the best interests of the profession or of the general public, that the present assumption of responsibility on the part of district local authorities for any structural building defect should continue. Verulam

A requirement to check the widths of load-induced cracks is now a feature of current British Codes for structural concrete. However, the theoretical background to the procedures given in the Codes has not been published in a readily available and reasonably condensed form. This paper attempts to rectify this situation by presenting the derivation of a theory for the prediction of cracking in hardened concrete. This theory is shown to be a logical development of earlier theories, and is based on the extensive research program carried out at the Cement and Concrete Association over the last 14 years. The theory forms the basis of many Code crack prediction equations, and the derivation of these is discussed. A.W. Beeby