DEL042 1221374 Towards improving soft sediment / tailings consolidation

Aanleiding van het project

Sediment waste of mine processes (tailings) as well as dredged sediments are deposited in basins, pits, or beneficially re-utilized to build new lands (e.g. Marker Wadden), to improve resilience of flood defences or enhance habitat restoration.
The ability to improve the understanding and prediction capabilities of the sediment consolidation dynamics as well as the characteristics and properties of the resulting deposits (e.g. strength, total settlement and time scale), especially at the fluid / solid interface is critical to reduce cost and risk of these activities. Current knowledge and predictive tool in the fluid / soil interface is nowadays limited. This project aims to contribute to close this key knowledge and tool gap.

Doel van het project

One of the key challenges in Delta Technology is related to possibilities of building on and with soft material. Soft materials (e.g. from dredged material and mine tailings) can be reused to form robust water defences, enclosure dams and for land building. The material can be used to combat settlement in Sustainable Delta Cities, as a cost-effective material for flood defences, and as the basis for nature-based land reclamations like Marker Wadden. As such, \”Bouwen met Slib\” has been identified as an important innovation to strengthen the international position of Dutch engineering companies.
Via the analysis of extensive laboratoy and bench scale data on soft sediments consolidation, this project will deliver new understanding on processes that drive consolidation of ultra-soft sediments.

Uitgevoerde activiteiten

1) Data Collection and Analysis. Most of the data, critical basis for this study, will be provided by Barr. This will be integrated with literature and Deltares soft sediments / tailings data.
2) Definition of a Physical Conceptual Model that indicates the most important processes that influence conoslidation of soft sediments, and highlight relevant theory and modeling tools.
3) (Optional, and depending on 1 and 2) Modeling of selected bench scale testing to verify theory.

Gerealiseerde resultaten

This project will inventorize and integrate the different processes that drive consolidation of very soft sediments / tailings, potentially connecting the fluid phase (e.g. flocculation and settling) with the solid phase (conoslidation and creep).
The results of the project will provide an improved understanding of soft sediments, mine tailings and dredged sediment management and reuse. Through partners such as Barr this will lead to an enhancement of international knowledge within the industry network.
This knowledge will be able to be utilized by the Dutch partners (e.g. dredging industry or RWS) on large on-going soft sediment projects to improve accuracy of design and reduce risks and cost (e.g. MarkerWadden, Kleirijperij).


The behaviour of soft sediments and slurries in basins, pits and land reclamations is surrounded by uncertainties. The availablility of new data, knowledge and measurements will allow a major advance in our understanding of this behaviour and in the ability to model and predict its future properties (e.g. strength and total settlement).
This project will connect fluid and soil knoweldge and processes, pushing the boundary of current knowledge and prediction capabilities. This project will make best use of the available knowledge and on-going research and development within and outside Deltares, and apply it using the data provided by Barr.


Project results and new knowledge developed will be made available in the public wiki site on the TKI DeltaTechologie site.

Project results will be presented at relevant conferences (e.g. sediments, mining or related areas). The theory developed will be part of the Master Thesis lectures at the Technical Delft University (e.g. Dr. Bernadette Wichman, and Pr. Cristina Jommi). This material will also be disseminated by Deltares at short courses.