Programme/program

It is very evident today that geotechnical engineering faces challenges of increasing complexity and scope. Efforts have been made in industry and in academia to address some of these challenges, contributing to the development of the current and future safe, sustainable and resilient society. This lecture focuses on the development of robust predictive tools to underpin the geotechnical design concerned with the lifecycle assessment of different types of infrastructure, illustrated by specific examples from the Speaker's research. The key for these developments is the consistent integration of the soil and ground characterisation with rigorous computational analysis and validation through field monitoring.

This talk will explore the emerging field of physics-informed machine learning in geotechnical engineering, with a specific focus on how the integration of fundamental soil mechanics, experimental and field data, and advanced computational methods can overcome limitations of traditional modelling approaches. It will highlight recent advances in embedding physics into data-driven architectures to achieve varying levels of physical constraint. Finally, the talk will examine new strategies for leveraging models of differing fidelities to enable more accurate, efficient, and generalisable predictions for geotechnical design and analysis.

In December 2022, a calamity occurred in the Prinses Margriettunnel near Sneek. One of the supports of this aqueduct in the A7 motorway appeared to have risen 6 cm, requiring the aqueduct to be closed to all traffic. Together with Rijkswaterstaat, Van Hattum en Blankevoort and VSF solved this calamity and ensured that this structure can be used again for years to come. This presentation will take you through the (re)design and realisation of the repair of the pile foundation, and the challenges that came our way.

Standards and guidelines/Standards and guidelines

13.30 - 13.50 Update Handbook Foil Structures - Ivo Huiskes (RWS)
Over the past two years, a team of specialists has worked on a thorough update of the 2009 Handbook Foil Structures. In this presentation, we briefly refresh what a foil construction is, explain the newly added chapters and share the most important new insights included in the revised version. This will give you a clear picture of the improvements and innovations in the handbook at once.

13.55 - 14.15 Guideline 'Bearing Capacity of open-ended steel pipe foundation piles' - Maarten Profittlich (Fugro) & Alfred Roubos (Port of Rotterdam Authority)
Since 2017, stricter calculation rules for foundation piles have applied, which in the Port of Rotterdam led to longer foundations and over 25% extra CO₂ emissions, without any practical problems. Large-scale tests were therefore carried out within the INPAD research programme, co-financed by the Port Authority. With an investment of EUR 4.5 million, around 25 million in construction costs and 13 kilotonnes of CO₂ were saved. The results closely matched an internationally developed, harmonised design method, which prompted an update of the CUR2001-8 guideline. During the Geotechnical Day, these new insights and their impact will be presented.

Foundations/Foundations

13.30 - 13.50 Test loads on weak loam soil improved with expansion resin - Robbert Melis (Uretek)
In Belgium and the Netherlands, settlement problems are increasingly occurring in buildings with shallow foundations. As an alternative to traditional, often quite invasive solutions, the minimally invasive injection method with expansion resin was investigated. At the Buildwise test site in Limelette, load tests were carried out on four foundation blocks in calcareous loam soil with low cone resistance. Three foundations were injected, one served as a reference without injections. The load tests, carried out in accordance with NBN EN ISO 22477-1, show that injections can greatly reduce settlements and significantly increase bearing capacity.

13.55 - 14.15 Test loads on 57-year-old tension piles - Lennart Stelling (Witteveen+ Bos)
Recently, test loads were carried out on tension piles in the port of Rotterdam. These involved tensile tests on three existing, 57-year-old tension piles, with the aim of gaining insight into the actual geotechnical holding power of the tension piles of the adjacent quay wall. The set-up of the tests, as well as the test results and a translation into practice will be explained in more detail during the presentation.

Grondgedrag/Soil behaviour

13.30 - 13.50 Key Design Lessons Learned of the Princess Elisabeth Island - Reza Shahbazi (Haskoning) & Marques Da Rocha José Miguel (DEME group) (English)
Princess Elisabeth Island (PEI) will be the world's first offshore energy island, centralizing 3.5 GW of Belgian offshore wind power. Its foundation comprises 23 sand-filled caissons on a rock mound. The design addressed key geotechnical challenges through large-scale hydraulic testing and advanced PLAXIS flow-stress modelling. Lessons include wave flow effects on stability, staged settlement analysis, caisson joint design, and tolerances for uneven rock surfaces. These approaches minimised uncertainty, optimised rock and concrete use, and ensured robust long-term stability. The project demonstrates how coupling physical tests with FE simulations delivers reliable, efficient offshore infrastructure.

13.55 - 14.15 Real-time Data Integration and Analysis in Backward Erosion Piping Experiments Using a Digital Twin - Diana Portillo Arreguin (Deltares) (English)
This presentation shows the development and application of a Digital Twin to support a medium-scale backward erosion piping (BEP) experiment. The system integrates real-time sensor data into a dashboard to visualise pressure distributions, estimate gradients and flow rates, and monitor critical conditions. The digital twin enabled near real-time interpretation and informed decisions during the test. The digital twin also streamlined post-processing and improved data consistency. Designed with a modular structure, it is adaptable to other experimental or field-scale applications. The experience demonstrates the value of digital twins in enhancing experimental control and understanding of complex failure mechanisms.

Metenen weten/Measurements and knowledge

13.30 - 13.50 Communication cable as kilometre-long geotechnical sensor - Agnes van Uitert (ProRail)
Fibre-optic communication cables are located along ProRail's tracks. The technology to perform measurements or monitoring with such a fibre-optic cable has greatly improved in recent years, as the interrogators that read the cables have become better/stronger in recent years. At ProRail, research has been done over the past five years on how to further exploit this technique, including in the geotechnical field. For example, a track section was monitored for deformations and the wave velocity along the track was determined on several track sections, including a longitudinal profile of the subsurface. In the presentation, we share our results and experiences. For example, research has been conducted on measuring deformations in our runway bodies and fibre optic cable has been used to establish a (ground) profile based on the shear wave velocity.

13.55 - 14.15 How to determine the compression constant of a discarded refrigerator - Nathan de Baat (Sweco)
Commissioned by Energie Kenniscentrum Leeuwarden, a circular building was built in 2019 on top of the closed waste repository Skinkeskâns in Leeuwarden. The waste storage consists of an approximately 10 m thick package of waste and is equipped with a sealing construction with a thickness of 1 m. The top of the waste storage is approximately 11 m higher than the surrounding ground level. Because of the present sealing construction, only a foundation on steel was possible and no soil investigation could be carried out. But how do you then determine the bearing capacity and deformation behaviour of the waste. The presentation will explain how the design for the foundation was arrived at on the basis of measurements.

Standards and Guidelines/Standards and guidelines

15.00 - 15.20 Guideline 'CUR166 Handbook for Sheet Piling Structures' - Rodriaan Spruit (Municipality of Rotterdam)
Since the end of 2019, a lot of hard work has gone into a new version of the "Handbook for Sheet Piling" (CUR166). Since 1993, 6 versions have now been published. Versions 1, 2 and 3 (1997) represent the first phase in the development of the handbook, followed by a more extensive update (second phase, versions 4 , 5 and 6 (2012)). This version 7 (2025) involves a rigorous update of the Handbook (third phase).

The main changes that will be explained in the presentation:

- Primarily a digital book.
- Connection to the (new) Eurocode (2024) regarding safety philosophy and confidence levels.
- More attention to 'logical thinking' in design.
- More attention to environment and manufacturability in design.
- More attention to hydrology.

15.25 - 15.45 Standard 'National Annex Eurocode 7' - Jan van Dalen (DaeD Engineers)
Several committees are currently working on an update (second generation) of our National Annex. Jan van Dalen takes us through the current state of affairs in terms of the adjustments provided for herein.

Foundations/Foundations

15.00 - 15.20 Extraction of driven cast in-situ (DCIS) pile casings: comparison between theoretical and measured extraction forces - Matteo Ambrosi & Niels de Vos (IQIP) (in English)
This presentation investigates the extraction phase of driven cast in-situ piles, focusing on the forces involved in removing steel pile casings after concrete placement. The study compares theoretical shaft resistances and tension capacities with actual extraction force measurements from field data, assessing potential factors influencing casing extraction, including the role of high-frequency, low-energy hammer blows.

15.25 - 15.45 Innovative digital teaching methods in the revamped Master programme Geotechnical Engineering at TU Delft - Ronald Brinkgreve (Delft University of Technology/Seequent - The Bentley Subsurface Company)
The Master track Geotechnical Engineering is part of the revamped Master programme of the Faculty of Civil Engineering and Geosciences. It includes more digital applications and is divided into modules, each consisting of related subjects (units) with an overarching assignment. In the second year, there is a choice of projects, electives, and cross-over modules, after which the year is completed with a graduation assignment.

The Master track Geotechnical Engineering provides students with the necessary fundamental knowledge of soil behaviour, geology, experimental and numerical methods, as well as knowledge of geotechnical applications and implementation methods. The programme pays considerable attention to modelling, programming, and working with data. The presentation will include examples of innovative digital teaching methods used in this programme.

Soil behaviour/Soil behaviour

15.00 - 15.20 Geotechnics and Sustainability: Together towards smarter design - Jeroen Beute (Fugro)
Sustainability starts underground. The geotechnical consultant plays a crucial role in translating complex geodata into safe, feasible and cost-efficient designs. At a time when the environmental burden is becoming increasingly heavy, there is a growing need to link geotechnical engineering to sustainable responsibility. Testing design choices also for their environmental impact creates new insights and opportunities: from use of materials to working methods. This requires a broader view and encourages thinking in lower-impact alternatives. In this presentation, we will use practical examples to show how geotechnics and sustainability can go hand in hand - and how we, as a sector, can make the difference together.

15.25 - 15.45 Challenges and Solutions in Dredging and Reclamation with Cohesive Materials - Joris Bol (Boskalis) (in English)
The use of cohesive sediments in reclamation projects is becoming increasingly common throughout the world. This is partially due to a lack of competent (granular) materials, but also due to a more circular mindset. This presentation gives an overview of the impact of applying cohesive sediments, from a dredging, reclamation, and soil improvement perspective. Different work methods and their opportunities and challenges are highlighted, together with the impact on further ground improvement methods.

Measuringand knowing/Measurements and knowledge

15.00 - 15.20 Unearthing the hidden potential in ground investigation data by converting to geospatial databases - Joost Gevaert (Bedrock) (in English)
If not locked inside a PDF, ground investigation (GI) data is often locked in structured text files like AGS, GEF, etc. This creates barriers as geotechnical engineering becomes increasingly data-driven and automated. While these formats differ structurally, all GI data can be expressed as related tabular data (locations, in-situ tests, samples, lab results) with geospatial components (Easting, Northing, elevation).

Bedrock, an open-source Python library, transforms GI data from legacy file formats into 3D geospatial databases (e.g. GeoPackage), thereby unlocking the (data-)scientific and geospatial open-source ecosystem. This simplifies (web-based) GI-data visualisation and interoperability with GIS, BIM, parametric design, and dashboarding software.

15.25 - 15.45 Overconsolidation by creep - case study Rijksweg 4 Delft-Schiedam - Herbert Polinder (Boskalis)
As part of the research programme TKI Improving Subsidence Projections , Boskalis has analysed oedometer tests. The aim of this analysis was to determine the developed boundary stress and overconsolidation ratio (OCR), to compare with model predictions. Rijksweg 4 Delft-Schiedam offers an exceptional opportunity to validate the degree of overconsolidation due to creep. This is because a preload was placed in the 1970s and has been present for about 40 years. Around 2010, samples were taken and laboratory tests carried out before resumption of work. The presentation at the Geotechnical Day will discuss the findings of the analysis carried out, including the influence of sample creep.

Panel: Jan van Dalen (Daed Ingenieurs), Flip Hoefsloot (Fugro), Ivanka van Berkom (Ingenieursbureau Amsterdam), Richard de Jager (Boskalis) & Cor Zwanenburg (Deltares). Moderator: Alex Greeuw (Dura Vermeer)