Eurocode 7 Section 8 - Ground anchors: development of the UK National Annex

摘要

When Eurocode 7 (EC7) was first published in 2004 it contained a Section 8 on design of ground anchors. This was widely considered to be inadequate and has had very little use. In 2013, a revised version of Section 8 was approved by the European committee on EC7 (CEN TC205/SC7), requiring a revision to the UK National Annex subsequently published by BSI (July 2014). The new code requires designers to show that anchors will perform satisfactorily in service conditions and will also prevent failure in the supported structure (ultimate limit states) in more onerous conditions than those checked historically, defined by partial factors. These requirements are to be demonstrated by testing the anchors, the code taking no account of calculated anchor capacities. This paper reviews the implementation of the new Section 8 using the revised UK National Annex, discussing the rationale that led to choices of partial factors and acceptance criteria. The separate consideration of service and ultimate requirements proved to be particularly challenging in relation to testing regimes, since it was considered undesirable to make these more onerous than those of BS8081. The use of the new National Annex is illustrated by examples.