MPM-Flow project

Understanding flow slides in flood defences (MPM-Flow)

This is the website of the MPM-Flow project (Understanding flow slides in flood defences) which is funded by the Dutch Technology Foundation (STW) dealing with the experimental and numerical simulation of large deformations involved in flowslides and the modelling of soil-water interaction. The MPM-Flow project connects two academic participants with several partners in a consortium which engages key public and private stakeholders in the sector.

Flow slide, Rogers, Missouri University, USA

Project coordinators:

• Prof.dr.ir. W.S.J. (Wim) Uijttewaal, Delft University of Technology, Faculty of Civil Engineering and Geosciences, Department of Hydraulic Engineering, Section Environmental Fluid Mechanics
• Dr. J.T. (Joris) Eggenhuisen, Utrecht University, Faculty of Geosciences, Department of Earth Sciences, Eurotank Flume Laboratory
• Prof.dr.ir. S.N. (Bas) Jonkman, Faculty of Civil Engineering and Geosciences, Department of Hydraulic Engineering, Section Hydraulic Structures and Flood Risk
• Prof.dr.ir. C. (Kees) Vuik, Delft University of Technology, Faculty Electrical Engineering, Mathematics, Computer Science, Department of Applied Mathematics, Section Numerical Analysis

More information about STW projects can be found at:
Visit the STW website

More information about the MPM-Flow project on the STW website can be found at:
Visit the MPM-Flow project on the STW website

More information about MPM-Flow? Alexander Rohe or Mario Martinelli

Project summary

Research perspectives
During a flow slide, large amounts of soil move down an underwater slope. A flow slide is able to remove an entire dike or dune section which poses a severe threat to the water safety of low-lying countries (see picture above). The ability to predict flow slides is an important asset for the design of flood defence measures, their construction, maintenance and safety assessment; even more so in view of intensifying land use and the impact of climate change on low-lying coastal areas worldwide. Flow slides are not yet well understood. Their study requires an integrated approach of fluid and soil mechanics: soil movement induces turbulent water motion which in turn interacts with the eroding soil surface. Currently, such an integrated approach is lacking. Studies so far mostly rely on empirical approaches that apply to specific circumstances only and use considerable simplifications. Physical experiments involve high costs as scale effects necessitate large test facilities and such tests often only allow predictions for specific projects. This makes the safety assessment of flood defences and the development of measures to prevent flow slides difficult and costly.

In the current interdisciplinary project, an integrated numerical solution for the simulation of underwater flow slides from initiation up to deposition of sediments will be developed through enhancement of a numerical method, the so-called material point method (MPM). Laboratory experiments will be performed to gain deeper insight into soil and fluid mechanical processes that occur at the onset of and during flow slides. They further serve for the validation of the developed numerical solution method. New physics-based models for soil-water interaction, soil heterogeneity and turbulent flow as relevant to flow slides will be formulated and existing models will be extended. They will be translated into purpose-built, efficient algorithms to be integrated into available MPM Software.

Utilisation perspectives
Measures taken in the Netherlands in recent years to counteract flow slides involved costs amounting to M€ 100. Results of the current project will allow an accurate and site-specific evaluation of the vulnerability of flood defences to flow slides. This enables integrated probabilistic safety assessments of flood defences - and also an estimation of the post-failure ability of a flood defence to prevent flooding. Results of this project will thereby allow for much more refined and thus economical maintenance works.

The devised enhanced MPM Software is a 3D generic numerical method for integrated geotechnical and hydraulic analyses that can also be applied to other erosion processes than flow slides. It will for example also be of benefit to the offshore industry. Numerical analyses will help to raise the level of confidence in innovative technologies, e.g. for scour protection, protection of offshore pipelines, dredging and the exploration of hydrocarbon reservoirs. Furthermore, advanced mathematical solutions developed in the frame of this project are expected to find their way also into other software for geotechnical applications.

With regard to academia, this project prepares the ground for future high-level national and international collaborations between current project partners and academia as well as the high-tech industry. Dissemination of research results covering three disciplines are expected to distinguish the MPM Research Community as outstanding worldwide. This project will provide students with insight into world-leading research and cutting-edge technology thereby raising the level of their professional training. This provides companies of an innovative key industry branch with the needed skilled labour force.

Users will benefit from:

• Bringing the MPM Software to practice for analyses of flow slides and other erosion problems;
• Physics based models for geo- and fluid-mechanical processes of flow slides, turbulent flow, soil erosion, sediment transport and deposition, soil heterogeneity;
• Novel mathematical solutions to complex, large-scale simulations.