The value of a project and business is partly determined by the degree of sustainability

Contemporary issues that present challenges and require innovative, working solutions are digitalization, sustainability, energy transition and climate adaptation. Consultancy and engineering firm Lievense has these four current themes at the center of its services. Nowadays, the value of a project and company is partly determined by the degree of sustainability. Lievense strives to contribute to sustainable solutions for infrastructure, construction and environmental issues and has set itself sustainability ambitions.

Lievense is (has been) involved in several projects at different levels in which circularity plays an important role. In Friesland and Groningen, Lievense has worked on the following projects, among others, in which efforts have been made to reuse (building) materials.

Pumping station Fallingabuorren in Ferwoude
Wetterskip Fryslân is responsible for water management in the province of Friesland and the Groningen Westerkwartier. Commissioned by Wetterskip Fryslân, Lievense conducted a study on the use of existing concrete in new concrete construction. The result of this study includes the development of a flow chart to determine the permitted percentage of reuse of concrete granulate per object. This schedule lists the requirements that the concrete aggregate must meet and the consequences. A distinction is made between the reuse of concrete structures still to be demolished and the application of concrete granulate in the concrete mix. The knowledge was applied to the project pumping station Fallingabuorren, where an existing pumping station was demolished and the concrete was then reused in the new concrete structure. 

The effect of applying concrete aggregate instead of "normal" aggregate is strongly determined by the quantity. What determines the maximum amount of concrete aggregate is the specific performance required of the concrete. For example, the strength, environmental, and consistency class and the application. To achieve the circular goals, Lievense prepared both the preliminary design, final design and accompanying RAW specifications. The pumping station was realized in 2018 by Oosterhuis BV from Nijeveen.

Pumping Station Fallingabuorren Ferwoude.

Bridge Aldwaldmersyl in Oudwoude
For the Northeast Friesland municipality, Lievense conducted a study on the application of a second-hand bridge in collaboration with OHPEN Ingenieurs, Farsk Architects and NHL Stenden University of Applied Sciences.

The Aldwaldmersyl is an old lock in the Wâlddyk, a slack dike north of Kollum in northeastern Friesland. The existing bridge is at the end of its service life and has insufficient carrying capacity for today's traffic. Preference was given to a circular solution, namely utilizing a second-hand bridge. The halyard section of an old bridge from hamlet Ritsumasyl was considered potentially suitable to replace the bridge at Wâlddyk in Oudwoude.

The idea to reuse an old bridge arose from an innovative collaboration between government, education and business. Parties involved in this project included consulting and engineering firm Lievense, DDFK Municipalities, NHL Stenden, FARSK, Royal Oosterhof Holman and OHPEN Engineers. All involved recognized the need to reuse scarce resources and break away from traditional forms of cooperation.

The feasibility study, which provides insight into how the renewal of the bridge in Oudwoude will come about, was concluded with a positive conclusion. An incorporation plan was then drawn up in which all the steps of the bridge's installation were described in detail. Afterwards, it turned out that the second-hand bridge deck contained chromium-6 which ultimately led to the non-use of this bridge deck. The existing bridge is largely maintained. Lievense is providing the guidance for the structural design.

This project demonstrated that it is possible to implement sustainable initiatives in a relatively short period of time. The focus in this project was on the goal and less on possible obstacles, simply because the obstacles were not known beforehand. With the "Aldwaldmersyl Second Hand Bridge" project, the project team has shown that they are at the forefront when it comes to reusing large building materials. 

Existing bridge Aldwaldmersyl. (Image: Vliegend.nl BV)

Amalia tunnel Julianaplein in Groningen
In 2008, the Julianaplein in Groningen was reconstructed. This included the construction of the Amalia tunnel especially for cyclists and pedestrians. Within the D&C contract, the Amalia tunnel was designed by Lievense in prefab elements that were connected by post-tensioning. 

With the arrival of the southern ring road in Groningen, the Amali Tunnel must be removed. With the knowledge of today, the design lends itself well to reuse. Given the minor age of the tunnel, it will be dismantled and reused at another location within the municipality of Groningen. 

In the new situation, it is no longer possible to connect the tunnel elements in the original way and guarantee watertightness. Therefore, it was decided to construct above the groundwater level on a (underpinned) concrete floor. The feasibility study of reusing the tunnel is currently being conducted by Lievense.