Heijmans and CyBe Construction have printed two formworks with a 3D concrete printer. It is the first time in the Netherlands that construction elements have been made in this way. The printed formwork remains part of the construction element and is therefore a form of permanent formwork. The two companies carried out the test to explore possible 3D-printed formwork applications in civil engineering (road and hydraulic engineering). One of the formwork elements has been placed in front of the head office of Heijmans in Rosmalen.

‘Although the technology still requires further testing and refinement, 3D concrete printing mainly provides the necessary opportunities,’ says Jurre van der Ven of Heijmans. ‘Our aim is to print a double curved concrete formwork, which we will fill with reinforced concrete, and then use it to construct a bridge or a viaduct, because if an element is strong enough for such heavy constructions, it can be further developed and used for residential building. The tests we have recently carried out were successful.’

‘From the test on the first construction element it appears that the characteristic value of the concrete we printed (CyBe Mortar) is greater than previously calculated. We are extremely satisfied with this,’ says Berry Hendriks of CyBe Construction. ‘From practical research and tests of this nature we see that the technology is becoming more widely applicable. Above all, we notice from this that the advantages of 3D concrete prints are becoming more visible. Ultimately, it will help us to facilitate the sector with this technology so that construction can be carried out faster, cheaper and at a higher quality.’

Heijmans and CyBe have printed two concrete formworks. The first 3D print was a hollow formwork (1.25 metres wide, 35 cm deep and 3.1 metres high), which was filled with water to establish the maximum ‘formwork load’. It took approximately 30 minutes to print the formwork.

The second formwork has a straight and a double curved side and is 2.5 metres high. During printing, the bottom half of the curved side was given a smooth finish. On the one hand, this was done to see how flat and smooth printed concrete is after treatment, and, on the other hand, to inspect the growth of moss and algae. The formwork (filled with concrete) was placed in front of the head office of Heijmans and was printed in approximately 25 minutes.

Clients are increasingly demanding more complex designs and forms for houses and structures such as viaducts. This requires a lot of effort in terms of implementation and the design. These complex forms can be made through the traditional process; however, it costs a lot of design time and man hours to implement. 3D printing a concrete formwork, or even an entire construction, offers the potential to make free, organic forms of equal quality, but at lower costs (up to 50% lower).

Heijmans and CyBe anticipate using a printed formwork element in a project by mid 2017.