Eurocode 7 has created a healthy debate on the way ahead for geotechnical
Codes of Practice. The debate is hotting up and geotechnical practitioners
seem to be divided in their opinions of the relative merits of Eurocode 7
and the current British Standards. However, unlike the Euro currency issue,
we do not expect to have a referendum on the use of Eurocode 7!
My point is that at present designers are faced with diverse codes and
guidelines, which often lead to different results. While this is a natural
development and undoubtedly has many advantages, it can be confusing
particularly for young engineers.
Take for example the problem of retaining wall design. Most commonly used
textbooks still use the conventional approach that relies on the provision
of adequate overall or 'lumped' factors of safety against potential failure
mechanisms. On the other hand, the British Standard BS 8002:1994, Code of
Practice for Earth Retaining Structures, adopts the philosophy of limit
state design. It relies on worst credible design assumptions but does not
impose any special requirements as to the manner in which the safety and
stability of the structure may be achieved, whether by overall factors of
safety, partial factors of safety, or by other measures. Eurocode 7 is also
based on the philosophy of limit state design but adopts characteristic
design parameters and provides safety margins by the use of partial material
and load factors. CIRIA's recent publication, Modular Gravity Retaining
Walls - Design Guidance by Chapman et al. (2000), uses both Eurocode 7 and
BS 8002 but places more emphasis on Eurocode approach.
Clearly the most important aspects of any design are safety, serviceability
and economy. All design concepts aim to produce a design that would ensure
serviceability and safety of the structure throughout its design life. As
such, economy appears to be the prime consideration and Eurocode 7 may have
the edge in this respect. But does this simple criterion solve the problem?
In my opinion, no!
I would appreciate any comments you may have on this subject.
Regards
Mahmoud I Alsayed
Halcrow Group Ltd
The Octagon, 35 Baird Street, Glasgow G4 0EE, UK
Tel. +44 (0)141 552 2000
Fax +44 (0)141 552 2525
mailto:[log in to unmask]
http://www.halcrow.com
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The views expressed above are personal and do not necessarily represent
official Halcrow policy.
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Visit our website at http://www.halcrow.com
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