Circular project concrete Port of Antwerp

Resolving bottlenecks to eliminate land surplus in Antwerp region

Major infrastructure works within the Extra Container Capacity Antwerp (ECA) project will result in significant soil surpluses in the Antwerp region between now and 2030. Port of Antwerp aims to approach this project as sustainably as possible and intends to (re)use these soil surpluses to produce project concrete: customized concrete departing from known certified compositions. However, there are several legal and economic issues hindering the valorization of mixed sands (as well as recycled and artificial aggregates) in project concrete.

Through this project, we aim to find a solution to these challenges and apply it in a Proof of Concept: the design and tendering of the second tidal dock within the ECA project. In this project, the concrete volume is large enough to define project concrete made with mixed sands/recycled and artificial aggregates. The quality of the project concrete is demonstrated through a custom-made testing program.

The second focus of this project is on further building trust among all chain partners involved in the valorization of circular materials in project concrete. For this purpose, we scheduled various consultation moments, both to identify pain points and to gain trust.

In addition, we also organized various consultation forums with the working groups responsible for disposing of the soil surpluses and with the ECA project team.

Haven van Antwerpen-Brugge

Partners Vanbreda Risk & Benefits NV, WTCB (Buildwise), Kratos Law





  1. We were able to induce a mindshift among insurers: the two main Belgian construction insurers are willing to commit to further consideration of alternative (quality) criteria to determine the insurability of the project.
  2. We can determine the Total Cost of Ownership and increase trust among contracting authorities to include circular initiatives in specifications and award criteria. The uniform evaluation of bids remains a challenge.
  3. We developed a tool for soil valorization, allowing us to determine the potential applications of soil based on excavated soil samples according to technical (standardized) requirements.
  4. We organized a workshop on Circularity in Tendering attended by other contracting authorities (e.g., Lantis, B-Post...). In addition to a theoretical presentation, there was also ample opportunity for exchanging experiences and tips.


  1. For such projects, it is crucial to involve insurers in the preliminary phase, allowing traditional risk-averse thinking to be converted into risk appetite.
  2. The current legal framework provides opportunities for innovation and circular procurement, but it is up to the contracting authority to include these in its procurement documents and to adapt them. There is no quick innovative circular solution available in the regulations; this is bespoke.
  3. Flexible contract models offer opportunities but are not without drawbacks. The litigation over changes in the Implementation of Public Procurement Legislation Decree must always be respected.
  4. For large tendering files and major infrastructure projects, we must move away from the traditional tendering process. It is important to allocate sufficient time for a preliminary phase with a multidisciplinary approach and involvement of stakeholders.
5 proven locations
2 workshops
1 international publication
1 market survey


In the ECA project, the concrete for the key wall of quay walls in the second tidal dock will serve as a testbed for project concrete with mixed sands. For this purpose, a trial setup will soon commence to investigate the behavior of project concrete with mixed sands in a maritime environment.

Furthermore, we will conduct a market research to survey contractors in order to align the logistical flow of excavated sands with the concrete demand for quay walls in the project area.

This will allow us to finalize the design phase and identify the challenges and opportunities related to the use of excavated soil in cement-bound applications. This will result in a comprehensive description of the tender requirements for the project concrete for the second tidal dock.

The results of this testbed constitute a first step in scaling up the use of locally excavated sands in various projects and applications in the future.