It was at a fateful AGS Committee meeting in 2015 that John Powell from Geolabs suggested that the AGS guide: The Selection of Geotechnical Soil Laboratory Testing might require some updating. The genesis of the guide stretches back some 25 years to previous AGS Committee meeting in 1993 where the need for such a guide was identified. Some 5 years later, with contributions from over 20 individuals the first edition of the guide was published in 1998.

After a slightly longer than anticipated gestation period, the AGS is pleased to announce the publication of the 2018 version of the guide, which can be downloaded here. Like most AGS publications, the guide is being published in electronic format and is available to download from the AGS website.

The updating of the guide has had its challenges – not least because no electronic version of the original publication could be found and neither were there originals of the numerous figure available. The remit from the AGS Committee was simply to update the guide where necessary and not to re-write the document. Therefore whilst the text has been updated by and large most of the original figures and the overall format of the have been retained.

When the working group embarked on a review of the guide it was heartening to have colleagues offering well-thumbed and slightly dog-eared versions of the guide to start the laborious task of scanning and retyping the document. Clearly many practicing engineers had regularly consulted the guide when preparing specifications and scheduling laboratory testing.
One of the key drivers in updating the guide was to reflect the gradual withdrawal of BS1377 and its replacement with BS EN 17892 in its various parts. The AGS recognises the evolving situation with regard to the publication of European standards and it is anticipated that periodic updates of the document will undertake to reflect this. The original publication includes a significant list of references, not just British Standards but also a significant number of ASTM as well as Russia, Danish and other national standards. The 2018 version cites the latest version of these standards.

Despite the fact that 20 years have elapsed since the first edition there are very few innovations and new forms of test that have emerged in the interim. This perhaps reflects the fact that the 1998 edition of the guide covered all of the modern testing techniques that were available at the time such as various small strain testing techniques, the use of bender elements and resonant column testing.

The contents list of the 2018 edition will be familiar to users of the 1998 edition. Changes of note include the re-titling of Chapter 8 which is now ‘Testing of Anthropogenic Soils’ and Chapter 9 –which is ‘Tests for Special Applications’. Chapter 9 is now split into two sections. The short section 9.1 on ‘Special Testing’ includes tests not readily included elsewhere in the guide, for example durability and testing of stabilised soils. However the majority of Chapter 9 comprises section 9.2 Advanced Geotechnical Testing. This section has been substantially reviewed updated and expanded and the original 14 pages of text now runs to some 20 pages. The AGS has Professor Chris Clayton to thank for producing this part of the guide – which not only benefits from Chris’s personal experience and knowledge but includes input from internationally renowned experts who Chris was able to call upon for their opinion and input. We are confident that experienced practitioners and those relatively new to the industry alike will find this a useful reference document for those contemplating use of advanced triaxial testing as part of their ground investigation.

Special thanks are extended to fellow members of the task group. Lynne Llewellyn (Structural Soils) and Geraint Williams (ALS Global) for updating several chapters as well dealing with many of the formatting challenges.

It is not intended that a further 20 years will elapse before the next version of the guide is published and the baton for the next update has already been handed to Neil Chadwick and the recently formed AGS Geotechnical Working Group.

The AGS Guide: The Selection of Geotechnical Soil Laboratory Testing can be downloaded here.

This article was contributed by Peter Boyd, Operations Director, Ground Engineering, AECOM and featured in the March/April 2018 issue of the AGS Magazine, which can be viewed here.