In November 1995 the Highways Agency published the August 1994 amendments to the Specification for Highway Works, A significant amendment which incorporates a complete re-write is Series 1600 on Piling and Embedded Retaining Walls, previously called Piling and Diaphragm Walling. The Agency has based this series on the Institution of Civil Engineers (ICE) Specification for Piling (1988) with modifications and the draft Institution of Civil Engineers (ICE) Specification for cast-in-situ retaining walls with modifications, The series has eighteen clauses, of which ten are new, All of the previous clauses that have been retained have been retitled and considerably amended, retaining little if any of their previous text, The new series includes new clauses to specify secant pile walls, continuous flight auger piles and king post walls, Testing warrants individual clauses and the previous clause 'Proof loading of piles' has been replaced by 'Non-destructive methods for testing piles' and 'Static load testing of piles'. In addition there are new clauses to specify 'Integrity testing of wall elements' and 'Instrumentation of piles and embedded walls', Many of the changes have been brought about because of significant advances in computer-controlled monitoring and recording of pile-installation processes, This has proven to be particularly significant for continuous flight auger piling, now specified for the first time by the Highways Agency, This paper has resulted from an in-depth study of Series 1600 of the Manual of Contract Documents for Highway Works and interviews with key personnel in the piling industry, all of whom have contributed significantly to the development and implementation of the new series, The paper will summarize the whole series but will comment in detail on only those clauses that are new.
