Citation on the award of Life Membership, March 2006
John received his BE from the University of Canterbury in 1964. Subsequently he obtained a Masters degree from the University of Colorado working with Professors Larry Feeser and Hon Yim Ko and from there a PhD from Caltech where he studied under Prof Ronald Scott. For his PhD John worked on attenuation and directivity effects in strong ground motion as well as on the evaluation of site response as indicated in recorded ground motions.
On completion of his PhD John took an academic appointment at the University of Newcastle in 1975. In 1977 he moved to the University of Canterbury, Department of Civil Engineering.
John’s research and professional activities have contributed to the NZ understanding of earthquake geotechnical engineering in a number of areas.
His most recent achievement is the CUSP seismograph, which is now in commercial production. His initial motivation was to develop a device that was inexpensive enough to be deployed in sufficient quantity to study mechanisms such as rupture propagation. The initial devices he and a student developed at Canterbury exploited the mass-produced accelerometers used to trigger automotive airbags. It is a tribute to their inspiration and hard work that the CUSP was selected from a handful of international contenders for regional strong motion recording in the GeoNet Project. John subsequently devised the layout of a Canterbury Regional Network, which has since been deployed by GNS and is operated as an integral part of the GeoNet system.
Some of John’s work on retaining structures was funded by the Structures Committee of the former Road Research Committee of the National Roads Board. This used shaking table tests to look at the displacements of a scale model wall, particularly the residual displacement at the completion of the shaking, induced by the earthquake motion. This was a contribution to the design of gravity walls based on the concept of the Newmark sliding block analysis. At about this time (1980) John contributed to the Society’s Study Group on the Seismic Design of Bridges leading the discussion and reporting on design earthquake loading. He was also involved with the discussions on earth retaining structures. (Study Group Papers published in September 1980 Bulletin.)
A practical problem posed by Latham Andrews led to an analytical study of the conditions under which fault rupture is diverted around buildings, backed up by laboratory experiments confirming the analysis. This work was then extended to the effect of ridges and hillsides in displacing the surface expression of faults, a result which has been adopted into common geological interpretation practice. John derived great satisfaction from seeing his original, simple analysis extended by members of the European QUAKER Project, following observation of rupture diversion in the 1999 Turkish and other recent European earthquakes.
Perhaps the most significant contribution made by John relates to the prediction of liquefaction. This he did in conjunction with Professor Rob Davis, his colleague from the University of Canterbury. Their work was based on the concept of the liquefaction being related to dissipation of energy in the soil. Parameters for the energy dissipation had to be linked with engineering seismology ideas about the spread of energy from the earthquake source. This thinking was developed at a time when the approach to liquefaction prediction was almost totally based on empirical observation and the use of the Standard Penetration Test results. Despite the fact that at present the empirical approach is undergoing something of rebirth, the energy dissipation approach has generated a whole raft of further research with the Davis and Berrill papers being standard references in the literature.
A further aspect of John and Robs liquefaction work was EQC funded research on the liquefaction risk in Christchurch – found to be significant.
Part of his interest in liquefaction involved work searching for past evidence of liquefaction in NZ. Investigations of sites in the Buller region which were known to have liquefied during the Murchison and Inangahua earthquakes provided valuable data on NZ conditions as did his work on the Landing Road bridge near Whakatane after the Edgecumbe earthquake. However, these investigations were based on cone penetration testing (CPT) rather than SPT.
Real soil profiles are inevitably layered and the rapid changes in layer properties are often encountered in NZ raise questions about the interpretation of CPT penetration resistance near layer boundaries – underlying soft layers might lead to underprediction of penetration resistance and hence overprediction of the possibility of EQ induced liquefaction. A method for handling this has also been developed and backed up by calibration-chamber experiments conducted in collaboration with his French colleagues in Paris and Grenoble.
More recently he has worked on the response of foundations in liquefied ground and presented a joint paper on this topic to the GeoEng 2000 conference in Melbourne co-authored by a Japanese colleague Professor Susumu Yasuda.
This listing of John’s activities would not be complete without noting his untiring student mentoring work and his constant efforts to find financial support for students.
In recent years John has been an adjunct professor at the European School for Advanced Studies in Reduction of Seismic Risk located at the University of Pavia in Italy.
As will be abundantly apparent to all here, this is a significant contribution to NZ earthquake engineering expertise and to the Society. The Management Committee were unanimous in their decision to appoint John a life member of the Society.