Summary:
Soil erosion is a worldwide problem responsible for the failure of buildings, bridges, dams, levees, culverts, and cliffs. The phenomenon at the particle level is first presented including measurements of forces at the particle level and the associated erosion function which links the erosion rate to the hydraulic shear stress. Whether to use the water velocity or the hydraulic shear stress is discussed next. The Erosion Function Apparatus (EFA) test, the Borehole Erosion Test (BET) and the Pocket Erodometer Test (PET) are described next. Charts are presented linking the erosion function to the USCS classification system and the critical shear stress to common soil properties. Erosion models are discussed, and the importance of the turbulence intensity is emphasized and quantified. The two main numerical simulations schemes are presented and applied to discover the link between the effective stress cohesion intercept and the critical shear stress. Applications of these fundamental concepts follow starting with bridge scour including scour depth predictions and the observation method. Other applications follow with levee overtopping, meander migration, earth dam internal erosion and cliff erosion. Mitigation of erosion through countermeasures is covered next with riprap first and then grass covers. Setting the soil erosion process in a probabilistic and risk framework comes next and software programs are listed before concluding.

Bio-Note:

Jean-Louis BRIAUD

Distinguished Professor, Texas A&M University, USA.

Professor Jean-Louis Briaud is a Distinguished Professor and Holder of the Spencer J. Buchanan Chair in the Zachry Department of Civil and Environmental Engineering at Texas A&M University in the USA, a Distinguished Member of the American Society of Civil Engineers, and a Professional Engineer. He received his Bachelor degree in France in 1972 and his Ph.D. degree from the University of Ottawa in Canada in 1979. His expertise is in foundation engineering and more generally geotechnical engineering. He has served as President of the American Society of Civil Engineers and President of the International Society for Soil Mechanics and Geotechnical Engineering. Among other awards, he has received the ASCE Ralph Peck Award from the USA, the CGS Geoffrey Meyerhof Foundation Engineering award from Canada, the Jennings Lecture award from South Africa and the Terzaghi Oration from India. Over the last 30 years, Dr. Briaud has conducted about 30 million dollars of research, most of which was on foundations, retaining walls, and soil erosion. He has supervised 73 PhD students and 101 Master students. He is the author of the 2023 book entitled Geotechnical Engineering, and the 1992 book entitled The Pressuremeter. He has published about 300 articles and reports in geotechnical engineering. He enjoys tennis, soccer, rugby, and plays jazz piano at the amateur level.

Summary:

Ralph Peck, 1969, in his seminal Rankine lecture noted that ‘anyone who practices the application of soil mechanics needs to be fully aware of the potential value of the Observational Method (OM) and needs to understand the prerequisites for its success’.  Peck noted how Karl Terzaghi reflected on his methods for solving practical problems during the early development of the OM. The OM is a powerful practical technique which can provide significant advantages for many civil engineering projects. When used effectively it can:

• Create major time and cost savings
• Increase safety and reduce project risks
• Enhance collaboration between client, design and construction teams
• Enable the construction industry to learn from experience and improve future practice

Unfortunately, despite this compelling list of advantages, the OM continues to be significantly under-used. Two key constraints are commonly used contract conditions and industry culture.

This lecture will explore the advantages and the limitations of the OM, using several case histories to illustrate the lessons learnt and review how key constraints (both technical and commercial) can be overcome. Several OM applications in the last few years will be discussed which highlight the immense power of new technologies in instrumentation/monitoring and numerical analyses to facilitate near real-time back-analyses. These technologies provide a platform for exciting new developments whereby OM could provide:

• ‘Intelligent digital twins’ for our future built infrastructure
•  The basis for ‘Adaptive Designs’ which enable a more effective balance between resilient infrastructure (to withstand climate change) whilst minimising cost and carbon during construction
• Accessible data bases on full-scale performance, providing an evidence base for more informed selection of design parameters for future projects.

The lecture will conclude with recommendations for OM practitioners.

Bio-Note:

Tony O’Brien is a Fellow of the Royal Academy of Engineering and was awarded the British Geotechnical Association’s Skempton Gold Medal for his contributions to Geotechnics practice. He is the Global Practice Leader for Geotechnics at Mott MacDonald and a Visiting Professor at the University of Southampton. He has provided technical leadership on several major projects across Europe, North America and the Asia-Pacific region and worked as an Expert Witness during litigation/dispute resolution. Tony has published widely and authored/co-authored best practice guidance, including CIRIA guide (C791) on advanced numerical modelling and recently published a book on “The Observational Method in Civil Engineering” and has contributed to several international ISSMGE committees, including TC206 (for The Observational Method). 

Summary:

The Lecture will cover a range of major research initiatives I was involved in over the past 3 decades on different aspects of sustainability innovations in geotechnical and geoenvironmental engineering under the three main themes of soil mix technology for land remediation, low carbon infrastructure materials and smart infrastructure systems.

Bio-Note

Abir Al-Tabbaa is Professor of Civil and Environmental Engineering at the University of Cambridge. She is a chartered civil engineer and a fellow of the Institution of Civil Engineers. She has over 30 years experience in both academia and industry. She is internationally renowned for her research work on sustainability within geotechnical and geoenvironmental engineering in the fields of ground improvement and land remediation. Particular areas of expertise include soil mix technology; stabilisation/ solidification treatments and in-ground barriers; low carbon binders and carbon sequestration; self-healing and self-sensing infrastructure systems and climate resilient infrastructure materials; and digital tools and life cycle analyses. She is a UK representative on the ISSMGE TC211 and TC307. She is the recipient of the ICE Reed and Malik Medal and represented the University of Cambridge at the World Economic forum in Davos. She has over 250 journal publications, and has co-authored two books and multiple book chapters. She has secured over £50M of research funding and has been involved in a large number of national and international research projects with significant involvement of and engagement with industry.

Summary:

Sound and stable transportation geotechnical infrastructure assets are crucial for mobility, efficient logistics, and enhancing the economic growth of a region or a country. Transportation geotechnics plays a major role in the development of sound infrastructure, as they are the primary interface that supports pavements, runways, embankments, and bridge infrastructure. Most of these infrastructure distresses are attributed to underlying geotechnical factors, designs that do not account for soil variability and reliable characterization, over-reliance on characterization that is not performance-based, and a lack of integrating and understanding weather and environment patterns into designs. This lecture describes some of these fallacies and their impacts on current transportation infrastructure design and their performance. This discussion will explore potential research solutions arising from major advancements that describe various innovative composite materials designed to enhance underlying soil properties, as well as advancements in durability studies to screen soil treatments and reinforcements. Field validation is key to understanding the effectiveness of these methods. The lecture will also cover new advancements and technologies, including remote sensing platforms such as uncrewed aerial vehicles (UAVs) and Interferometric Synthetic Aperture Radar (InSAR) data from satellites for health monitoring of the infrastructure. It will also demonstrate the application of machine learning models to process data, providing a better understanding of factors that lead to quick and reliable assessments of transportation assets, thereby enabling proactive management of infrastructure network systems. All these works presented in this talk are based on research works performed by the authors and the research student group.

Bio-Note:

Dr. Puppala is A.P. Florence and Wiley Chair Professor of Civil Engineering of Department of Civil Engineering at Texas A & M University. He was a former distinguished professor in the Civil Engineering Department at the University of Texas at Arlington (UTA), Texas. He has been conducting research on ground improvement studies using chemical binders and geosynthetics, in situ intrusive and remote sensing methods including drone technologies for site characterization and infrastructure asset management studies, and pavement geomaterial characterization studies as well as flood control structure performance studies. He successfully supervised 47 doctoral students and more than 50 master’s students. Dr. Puppala has been successful in generating large research grants from a wide variety of entities, including the Texas Department of Transportation, National Science Foundation (NSF), United States Army Corps of Engineers (USACE), US DOT University Transportation Research Centers Program, Department of Energy and others. Dr. Puppala served on Transportation Research Board (TRB Committees, ASCE GeoInstitute committees and is a current Chair of ISSMGE’s TC 307, Sustainability in Geotechnical Engineering. He also serves as associate editor of many esteemed journals including ASCE JGGE, ASCE Journal of Materials, Engineering Geology, Transportation Geotechnics and others.

K. TERZAGHI's seminal book “Erdbaumechanik auf bodenphysikalischer Grundlage” (Soil Mechanics Based on Soil Physics) was published in Vienna in 1925 and is considered to be the birth of modern soil mechanics. In 1928, K. Terzaghi founded the world's first university institute for Soil Mechanics at the Vienna University of Technology (today TU Wien). Vienna immediately became a “Mecca” for engineers interested in soil mechanics and foundation engineering. The Laboratory of Soil Mechanics, which served as a model for the establishment of similar institutes in many countries around the world, was, like TERZAGHI's lectures, a magnet for students, engineers, and scientists from all over the world from the early 1930s onwards. Numerous standard test methods for soil investigation were developed in the Vienna laboratory and are still in use worldwide today.

Image 1: Bust of Karl v. TERZAGHI, unveiled on March 31, 1967, in former Lecture Hall XVI at TU Wien, named after him. Donated by A. CASAGRANDE on the occasion of TU Wien's 150^th anniversary in 1965.

Image 2: Cover of K. TERZAGHI’s fundamental book on “Soil Mechanics based on Soil Physics”, published in Vienna in 1925.

Image 3: TERZAGHI test apparatus for producing the test specimens (a) and for investigating compression (b, c), outlined in TERZAGHI’s fundamental book “Soil Mechanics based on Soil Physics”, 1925.

Image 4: Compression apparatus  (oedometers) designed by K. TERZAGHI (right) and A. CASAGRANDE (left); originals of the first fabricates between 1929 and 1933.

Image 5: The TU Wien was founded in 1815 as the Imperial and Royal Polytechnic Institute by Emperor Franz I of Austria.

Time table:

Sunday, 14.06.2026 

Meeting point: 14:00, ACV  

Duration: approx. 3 hours

Group size: min. 15 (if the minimum number is not reached, we reserve the right to cancel the tour)

Price: € 75,-

Included services: Tour with a certified guide, Bus

_{Photo credits: 
Hundertwasserhaus: Foto von steffen wienberg auf Unsplash
Prater: Foto von Marie Rouilly auf Unsplash
Musikverein: Bild von geischlaeger0 auf Pixabay}

Time table:

Monday, 15.06.2026 

Meeting point: 13:30, ACV, or 14:00 In front of the Albertina at the Albrecht Dürer fountain

Duration: approx. 3 hours

Group size: min. 10 (if the minimum number is not reached, we reserve the right to cancel the tour)

Price: € 75,-

Included services: Tour with a certified guide, Entrance Treasure Chamber

_{Photo credits: 
Burggarten: Cristi Croitoru (iStock)
Panorama Hofburg: Meinzahn (iStock)
Albertina: © Orietta Gaspari - 2012 (iStock)
Michaelerplatz: arcady_31 (iStock)}

Time table:

Tuesday, 16.06.2026 

Meeting point: 08:30, ACV, or 09:00 Ice cream parlour on Schwedenplatz

Duration: approx. 3 hours

Group size: min. 10 (if the minimum number is not reached, we reserve the right to cancel the tour)

Price: € 85,-

Included services: Tour with a certified guide, tastings

_{Photo credits: 
Kaffeebohnen: Foto von Battlecreek Co􀆯ee Roasters auf Unsplash
Kaffeeröster: Foto von Marsela Christina auf Unsplash
Café Central, © WienTourismus/Christian Stemper
Café Diglas, © WienTourismus/Christian Stemper
Sacher Cake, Café Sacher, © WienTourismus/Paul Bauer
Apfelstrudel, © WienTourismus/Paul Bauer}
 

Time table:

Wednesday, 17.06.2026 

Meeting point: 14:00, ACV

Duration: approx. 3 hours

Group size: min. 10 (if the minimum number is not reached, we reserve the right to cancel the tour)

Price: € 145,-

Included services: Tour with a certified guide, Bus, Klimt Villa admission, Belvedere admission

_{Photo credits: 
Belvedere: Josef Muelleck (iStock)
Klimt "der Kuss": pixabay
Secession © WienTourismus/Christian Stemper}

Time table:

Thursday, 18.06.2026 

Meeting point: 08:30, ACV, or 09:00 Belvedere Quarter (main entrance, near Schweizergarten)

Duration: approx. 3 hours

Group size: min. 10 (if the minimum number is not reached, we reserve the right to cancel the tour)

Price: € 60,-

Included services: Tour with a certified guide

_{Photo credits: 
Volksgarten, Natural History Museum: © WienTourismus/Christian Stemper
Volksgarten, City Hall: © WienTourismus/Christian Stemper
Johann Strauss monument, Stadtpark: © WienTourismus/Paul Bauer
Volksgarten, Museums, Parliament: © WienTourismus/Christian Stemper}