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The current suite of BS Codes and Standards will, in due course, be almost entirely replaced by a system of Eurocodes and Standards published by BSI as BS ENs; it is expected that the replacement will be complete by about 2010TT.
The Eurcodes adopt, for all civil and building engineering materials and structures, a common design philosophy based on the use of separate limit states and partial factors, rather than ‘global’ factors (of safety); this is a substantial departure from much traditional geotechnical design practice. The geotechnical design Eurocode (EN 1997-1) provides one, unified methodology for all geotechnical design problems; an advantage of EN 1997-1 is that its design methodology is largely identical with that for all of the structural Eurocodes, making the integration of geotechnical design with structural design more rational.
Eurocode 7 consists of two Parts: Part 1 (BS EN 1997-1) -Geotechnical design – General rules and Part 2 (prEN1997-2) -Ground investigation and testing. Part 1 lays down the design principles and rules generally to be adopted, and has been published by BSI; Part 2 is not yet available.
It is important to understand that not all of the documentation covering geotechnical engineering in the EU Member States is included in the two Parts of BS EN 1997. There are or will be Standards for the field investigation and testing, and laboratory testing, of the ground and for the ‘execution of special geotechnical works’; these are being produced by different CEN Technical Committees from those that wrote EN 1997. There are also Standards for ground identification and classification written by an ISO Technical Committee which are being brought into the CEN system.
It is important to appreciate that BS EN 1997-1 is not a detailed geotechnical design manual but is intended to provide a framework for design and for checking that a design will perform satisfactorily; that is, that the structure will not reach a ‘limiting condition’ in prescribed ‘design situations’. The Code therefore provides,in outline, all the general requirements for conducting and checking design. It provides only limited assistance or information on how to perform design calculations and further detail may be required from other texts, such as standard soil mechanics books and industry publications.
The setting of levels of safety for buildings and civil engineering works, and parts thereof including aspects of durability and economy, are a matter for individual member states of the EU. Such national choice, as identified by a ‘Note’ in EN 1997, is made in the National Annex (NA). The NA for BSEN 1997-1 is now available for public comment and should be published by the end of 2006.
Both the NA and BSEN 1997-1 are available from BSI.
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Shortage Occupation List 