Colored concrete with VARIODUR 40 defines the artwork by LENI HOFFMANN

Since September 2025, the light-blue concrete sculpture MOXIE by artist Leni Hoffmann has been standing on the cultural island in Moers Castle Park. The work, which will be on display until November 2027, brings together art, material technology, and engineering.

The starting point of the project was the artist Leni Hoffmann’s wish to create a sculpture made of “sky-blue” concrete. Dyckerhoff played a key role in realizing the concept by supplying cement, concrete, and logistics support, as well as facilitating contact with the pigment supplier Harold Scholz & Co. GmbH. Following technical discussions, the selected pigment was Cobalt Blue G 2828 BB.

Dyckerhoff cement VARIODUR 40 (CEM III/A 52.5 R) from the Neuwied plant was used for the project. This cement type is suitable for producing high-strength concrete and, due to its naturally light color, provided the ideal base for achieving the desired shade.

Using this cement and the chosen pigment, various color samples were produced in the Leverkusen testing laboratory in collaboration with the artist. After reviewing the samples, the artist chose the strongest pigment concentration of 10% to obtain the most intense color brightness possible.

A total of 10 m³ of fair-faced concrete was produced at the ready-mix plant in Neuss, with a cement dosage of 420 kg VARIODUR 40 per cubic meter. Due to the sculpture’s very slender form – parts of it measuring less than 40 cm in diameter – the structural engineer specified a higher strength class to prevent damage during demolding. Instead of C25/30, concrete class C40/50 was used, enabling the piece to reach the required load-bearing capacity for safe erection after just seven days.

Because of the dense reinforcement and slender structural shape, Dyckerhoff selected a maximum aggregate size of 8 mm and consistency class F4. This provided optimum flowability, allowing even tightly reinforced sections to be filled evenly and without voids.

In mid-August 2025, the artist first defined the sculpture’s outline on the cultural island and marked its location for subsequent excavation. The trench was then hand-dug in the curved shape of the future structure by the artist and her five assistants. Over the course of several days, the formwork made of plaster was carefully built up by hand. Later, the release agent tested in the Leverkusen lab was applied. Finally, in mid-September, the casting took place after an experienced reinforced concrete builder had installed the required reinforcement.

Delivering the concrete and lifting the massive concrete figure from the ground turned out to be a highly complex logistical challenge. Due to local conditions – particularly an adjacent stream and limited space – the use of heavy equipment was necessary. After the curing phase came the impressive moment of the final erection: with the help of two Sennebogen telescopic crawler cranes and additional heavy-duty equipment, the approximately 19.5-meter-long and 4.6-meter-high sculpture was carefully lifted from the plaster mold without damage, leaving behind the broken formwork.

MOXIE was then precisely positioned upright, securely placed on its foundation, and solidly anchored. The remains of the plaster molds are still visible at the base of the sculpture. The artist deliberately chose to leave these elements in place to keep the production process visible – MOXIE appears to have “emerged” directly from the ground.

The result is a light-blue, organically shaped concrete sculpture that conveys both lightness and stability through its precise execution and material quality. One side appears organic, curved, and lively, while the other retains the intentionally flat surface resulting from the casting process.

Dyckerhoff, already an important partner in Leni Hoffmann’s demanding concrete projects in 2009 (Museum Ludwig Cologne) and 2012 (Kunstverein Mönchengladbach), once again combined artistic understanding and concrete technology in 2025 for MOXIE – creating a work that unites technical precision and artistic expression.

MOXIE can be admired on the Moers cultural island until November 1, 2027.

Photos: Leni Hoffmann, Yukiko Oyama, Manuel Franke, Copyright: Leni Hoffmann

For further information, please contact:
Isabel Derstroff, Tel.: +49 611 676-3173
marketing@dyckerhoff.com