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Events

• Nov

  13

  Osterberg Lecture- The Mechanics of Clays: A Micro-Inspired Perspective- Angelo Amorosi

  McCormick - Civil and Environmental Engineering (CEE)

  11:00 AM A230, Technological Institute

  EVENT DETAILS

  Abstract: Soil mechanics is a well-established discipline that has always put considerable emphasis on the physical characteristics of the studied materials, whose peculiarity lies in their granular and multi-phase nature. The substantial role played by individual grains and, when present, by their aggregates on the behaviour of the overall soil skeleton is nowadays well-recognised, at least qualitatively, highlighting the intricacy of the multi-physical interactions occurring at the micro-scale. These interactions increase as the grain size decreases, reaching maximum complexity in clayey soils. In standard practice most of the above microstructural features are often only barely considered when quantitatively describing the mechanics of clays at the continuum level, erroneously implying that the micro and macro scales are broadly independent. This is obviously not the case, as demonstrated by the vast amount of research aimed at linking microscopic characteristics to macroscopic patterns of behaviour that has characterised the entire history of soil mechanics, proposing qualitative or, more recently, quantitative means of bridging the gap between scales. Along these lines, the talk aims at providing an overview of some recent advances in micro-inspired constitutive modelling of clays. It first illustrates a review of multi-scale experimental evidence and its possible interpretation and generalisation in terms of internal variables, i.e. state variables that condense microscopic mean characteristics and make them suitable to be incorporated into a macroscopic constitutive modelling framework. In light of the above, the specific modelling approach based on Thermodynamics with Internal Variables is then outlined and specialised to the case of clays, illustrating some recently formulated constitutive models. The proposed theoretical framework proves to effectively allow the development of constitutive models that not only respect the fundamental principles of thermodynamics, but also directly benefit from our understanding of the complex microstructural features of clayey soils.

  Biography: Angelo Amorosi is Professor of Geotechnical Engineering at Sapienza University of Rome (Italy), where he graduated in Civil Engineering in 1992 and then obtained his PhD from the Department of Structural and Geotechnical Engineering. During his career, Prof. Amorosi spent several periods of study and research abroad, working at City University of London (UK), Technical University of Athens (Greece) and Oxford University (UK). In 1999, he became Lecturer and then Associate Professor of Geotechnical Engineering at the Technical University of Bari (Italy), where he worked until 2015. His research interests include experimental observations and mathematical modelling of the mechanical behaviour of clayey soils, the development of numerical integration schemes for plasticity-based constitutive laws, and the numerical simulation of various boundary value problems under both static and dynamic conditions, with a focus on natural and artificial slopes, earth dams, tunnels and masonry structures. Professor Amorosi has been invited to deliver numerous general and keynote lectures at internationally recognised congresses and symposia, as well as several seminars at prestigious academic institutions. He has been member of the editorial panel of Géotechnique and is currently member of the editorial boards of Acta Geotechnica and of the Italian Geotechnical Journal, also serving as reviewer for several international journals in geotechnics and mechanics.

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  TIME Wednesday, November 13, 2024 at 11:00 AM - 12:00 PM

  LOCATION A230, Technological Institute    map it

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  CONTACT Andrew Liguori    andrew.liguori@northwestern.edu EMAIL

  CALENDAR McCormick - Civil and Environmental Engineering (CEE)

• Jan

  6

  Winter classes begin

  University Academic Calendar

  All Day

  EVENT DETAILS

  Winter classes begin

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  TIME Monday, January 6, 2025

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  CONTACT Office of the Registrar    nu-registrar@northwestern.edu EMAIL

  CALENDAR University Academic Calendar

• Jan

  9

  TAM Seminar- An Impenitent Son Returns- Roberto Ballarini

  McCormick - Civil and Environmental Engineering (CEE)

  11:00 AM A230, Technological Institute

  EVENT DETAILS

  Abstract: Exactly 40 years ago I defended my dissertation in this building under the guidance of my mentors Leon Keer and Suru Shah. I cannot say it was “the very same” Technological Institute building because at that time our offices were not air-conditioned and the leaky windows were permeable to falling snow. Today I will describe how a bunch of clever and hardworking students and other collaborators have enabled me to use what I learned at Northwestern as a springboard for applying theoretical, computational and experimental mechanics to improve our understanding of the response (at multiple scales) of materials and structures to mechanical, thermal, and environmental loads. The illustrative examples include the use of microelectromechanical systems (MEMS) devices as platforms for structural testing at the micrometer and nanometer scales; bioinspired design of ceramic-matrix composites through the reverse engineering of the shells of mollusks; fracture mechanics-based design in civil, mechanical and aeronautical engineering; and stochastic buckling of thin-walled shells containing geometric imperfections.

  Bio: Roberto Ballarini, who received his NU doctorate in 1985, is Thomas and Laura Hsu Professor and Chair of the Civil and Environmental Department at the University of Houston, and Director of the University of Houston-Dalian Maritime University Institute. His multidisciplinary research focuses on the development and application of theoretical, computational and experimental techniques to characterize the response of materials to mechanical, thermal, and environmental loads. Ballarini is particularly interested in formulating analytical and computational models for characterizing fatigue and fracture of materials and structures arising in civil engineering, mechanical and aerospace engineering, materials science, microelectromechanical systems, biological tissues and prosthetics. He has published more than 130 papers in refereed journals, including Science, Nature and Proceedings of the National Academy of Sciences, and several of his research projects have been featured in the popular press, including the New York Times Science Times, American Scientist, Business Week, Financial Times, and Geo. Ballarini a Distinguished Member of ASCE, Fellow of ASME and of the Engineering Mechanics Institute, is Past-President of the ASCE Engineering Mechanics Institute and served as Editor of the ASCE Journal of Engineering Mechanics. He is recipient of the 2019 ASCE Raymond D. Mindlin Medal in recognition of outstanding research contributions to applied solid mechanics, and the University of Houston’s Global Faculty Award for his leadership in international teaching and research collaborations.

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  TIME Thursday, January 9, 2025 at 11:00 AM - 12:00 PM

  LOCATION A230, Technological Institute    map it

  ADD TO CALENDAR

  CONTACT Andrew Liguori    andrew.liguori@northwestern.edu EMAIL

  CALENDAR McCormick - Civil and Environmental Engineering (CEE)