Ziggy LubkowskiPerformance-based geotechnical earthquake engineering – How can we use it in practice?


Since the publication of SEAOC Vision 2000 in 1995 the topic of performance-based earthquake engineering has been a key subject for earthquake engineers. This has principally been focussed on structural aspects of design and less so on geotechnical aspects. The framework of performance-based design was adopted some 15 years ago in the International Standard ISO 23469 for seismic design of geotechnical structures. However, very little useful and pragmatic guidance is provided for the practising engineer. The one area in which strides have been made is for the design of ports and harbours. How can we best utilise this disparate guidance for real design work? It is well understood that the seismic performance of geotechnical works is significantly affected by ground displacement. Therefore, there is a requirement to accurately model the behaviour of geotechnical structures and estimate ground displacements. This leads to concern relating to the adequacy and accuracy of computer models to estimate soil behaviour and associated settlements or displacements. This paper reviews the current state of the practice in performance-based geotechnical earthquake engineering. It looks at key questions and concerns in implementing this approach. It also provides examples of how the approach has been applied to projects including ports, bridges and offshore structures and hence attempts to provide some practical design guidance.


Ziggy is a geotechnical earthquake engineer with over 30 years’ experience working at Arup. He has carried out seismic design, analysis and assessment for a range of structures in the energy, infrastructure, manufacturing and humanitarian sectors. He has acted as the seismic specialist for major projects such as offshore platforms in New Zealand and Caspian Sea, the proposed Çanakkale Bridge in Turkey, and the seismic and tsunami hazard assessment for the new Wylfa Newydd NPP. Ziggy was recently appointed a Royal Academy of Engineering Visiting Professor in Geotechnical Earthquake Engineering at UCL. He has been Chair of SECED and is heavily involved in the development of Eurocode 8.