2025 PGS Workshop & 21st G.A. Leonards Lecture
April 11, 2025
Krannert Auditorium, Purdue University
West Lafayette, IN
Engineering Frozen Ground: understanding the behavior of soil on freezing and thawing
Video of Lecture | Lecture Slides
Professor Giulia Viggiani
Cambridge University
The use of artificial ground freezing to form earth support systems has had applications worldwide. These cover a variety of construction problems, including the formation of frozen earth walls to support deep excavations, structural underpinning for foundation improvement, and temporary control of ground water in construction processes. At the same time, climate change driven seasonal freezing and thawing of soils in the northern hemisphere can have very detrimental impact on infrastructure. Freezing and thawing of a moist soil is a process coupling heat and mass transfer, which involve complex thermal, hydraulic and mechanical processes with significant mutual interactions. The lecture will describe an extensive and successful application of artificial ground freezing during excavation of some of the stations of Line 1 of Napoli Underground through loose granular soils and a fractured soft rock. Construction was accompanied by an intense programme of monitoring designed to measure and control the effects on adjacent structures, which, for its extension and completeness, represented a unique opportunity to collect field data on the performance of AGF. The lecture will describe the main phenomena that were observed during construction, and some of the analyses that were carried out to interpret different aspects of the process. Experimental observations on frost heave susceptibility carried out using innovative equipment will also be discussed.
Introduction by Marika Santagata, Purdue University
Giulia Viggiani is Professor of Infrastructure Geotechnics in the Department of Engineering of the University of Cambridge, where she is the Head of Civil Engineering, Academic Lead of the UKCRIC National Research Facility for Infrastructure Sensing, and a CoInvestigator and member of the Executive Committee of the Cambridge Centre for Smart Infrastructure and Construction. Before this, she was Full Professor of Geotechnical Engineering at Università di Roma Tor Vergata.
She has a Laurea in Civil Engineering from Università di Napoli Federico II and a PhD in Geotechnical Engineering from the City University in London. She has been Scientific Visitor at the Max Planck Institute for Mathematics in the Sciences in Leipzig, MTS Visiting Professor of Geomechanics at the University of Minnesota, Distinguished Visiting Scholar at the University of Macau, and Academic Visitor at Imperial College, working on the JLE-Link Project. Her role as a recognised expert in the field of geotechnical engineering for infrastructures has been acknowledged both at national and international levels. She has been invited to deliver General Reports and Keynote Lectures at several international conferences. She is an Italian chartered Civil Engineer and member of the ISSMGE, AGI and BGS. She currently chairs ISSMGE TC204 – Underground Construction in Soft Ground.
She has been involved in many infrastructural projects in Italy and the UK, including, e.g., monitoring building response to construction of the Jubilee Line Extension in London, the design and construction of Lines 1 and 6 of Napoli underground and of Line C of Roma underground, and the design of the foundations, anchor blocks and terminal structures of the Strait of Messina Bridge.
Presented in conjunction with the 21st Purdue Geotechnical Society Workshop - "Engineering the Ground: from fundamentals to applications"
Workshop Program | Presentation Abstracts | Event Photos
2025 PGS Student Committee
Support for the PGS Workshop and Leonards Lecture is provided by the following sponsors:
