The Nineteenth Mallet-Milne Lecture

Introduction

We are delighted to announce that Professor Gian Michele Calvi has accepted the invitation by the SECED Committee to deliver the 19^th Mallet-Milne Lecture next year. As with previous Mallet-Milne lecture nominees, this recognises Prof Calvi’s wide contributions to earthquake engineering theory, practice and education. The 19^th Mallet-Milne lecture will be delivered in the Telford Theatre in the ICE Headquarters in Westminster, London, on 28th May 2025.

Synopsis

Major seismic events over the last century or more have led to large numbers of casualties and damage to buildings and infrastructure. The loss of homes and livelihoods have often led to either mass exodus from an affected region, or the rapid construction of makeshift houses that are often of a lower standard than that expected of newly built permanent dwellings. Often intended to be temporary or “transitional” accommodation, this rapid reconstruction can often remain for decades or centuries after. The primary objective of this study is to evaluate the effectiveness of public actions taken after major seismic events, specifically in managing large numbers of displaced people and mitigating the social impact and indirect losses caused by interruptions to various residential services. Several notable examples from around the world are presented and discussed.

Having established that the response to this kind of emergency has generally been unsatisfactory and that a general approach to improving the situation is missing, the actions undertaken following the earthquake in L’Aquila, Italy, in 2009, are discussed, to investigate whether it is possible to derive approaches applicable in broader situations. This example shows that rapid construction of permanent housing was possible without compromising on the standards expected by modern building codes. This was achieved by using standardised designs for base-isolated platforms that effectively reduce the design seismic accelerations for multi-unit housing complexes built on top of them. Post-L’Aquila, this allowed effective quality control on the most critical component of the system – the base isolation system – while permitting multiple engineers and contractors to, in parallel, develop and implement the building designs, significantly expediting the post-earthquake recovery process.

Encouraged by this example, the remainder of the paper discusses how this idea can be further developed before the next major earthquake occurs, to enable even more rapid implementation in an affected disaster zone. The application of performance-based design procedures at a regional scale is examined, to establish how extensive the problem could be, i.e. whether estimates of the potential number and location of displaced people lead to a sufficiently clear picture to allow the appropriate authority in a country (e.g. the national civil protection department) to deal with it, developing detailed plans in peace (i.e. non-emergency) time. If this is the case, national or regional emergency plans can focus on a limited number of locations, considering that population concentration, event magnitude and fault distance are limiting the cases in which the expected homeless people are greater than significant threshold values.

A fundamental part of the study is devoted to the development of design approaches oriented towards rapid reconstruction, with the aim of completing high-tech alternative residential buildings. These buildings are characterized by a high level of seismic protection, continuity of use in case of strong earthquake, low levels of energy consumption, acceptable social and urban organization and potential for rational re-use following a reasonable emergency time, of the order of about ten years from past experiences. A key component of the solution is the application of seismic isolation. This approach aims to facilitate the use of different building construction technologies and the design and analysis of buildings by essentially eliminating the variability imposed by local input ground motion and soil conditions from the design process, and reducing the inertia force to a small fraction of gravity. Standardised base isolation solutions are developed, including technical details and a worked example to illustrate the feasibility and applicability of this approach.

For further information about the Mallet-Milne Lecture, SECED’s biennial prestige lecture, and its previous awardees, please see here.

Biography

Gian Michele Calvi (1957), is Professor at the IUSS Pavia, Italy, and Adjunct Professor at the North Carolina State University. He received a Master of Science from the University of California, Berkeley, a PhD from the Politecnico di Milano and an Honorary Doctorate from the University of Cujo, Mendoza, Argentina. He is the author of hundreds of research publications spanning diverse aspects of earthquake engineering, including seismic design and assessment methodologies for new and existing structures, with a special focus on masonry and reinforced concrete buildings and bridges; development of displacement-based seismic design methodologies; and seismic isolation technologies and their application. He has also been designer, consultant or checker for many structural projects, including the Rion-Antirion cable-stayed bridge (2883 m, in Greece), the Bolu viaduct (119 spans, in Turkey) and the new housing system developed in the aftermath of the 2009 L’Aquila earthquake, wherein 185 seismically-isolated buildings were constructed in just six months to rehouse the displaced population.

Professor Calvi is the founder of the Eucentre Foundation, the earthquake engineering research centre and laboratory based in Pavia, Italy, and of the ROSE School, the post-graduate training programme that has trained hundreds of engineers and researchers for more than two decades. He has been a member of the Board of Directors of the GEM Foundation and is the President Elect of the International Association of Earthquake Engineering (IAEE). He is also an associate editor of the Journal of Earthquake Engineering (Taylor and Francis) and has been an invited keynote speaker in tens of conferences, including two World and four European Conferences on Earthquake Engineering. 

Further information

Further information will be published in due course at the event link here.