Tight housing shortage vs. strict emissions rules: this start-up offers solution

Eindhoven-based Zavhy wants to make the construction industry more sustainable and digital with 3D printing of concrete (3DCP).

It is one of the biggest challenges in the Netherlands. On the one hand: the housing shortage, about which bureau ABF Research announced last week that it has risen sharply again (an increase of 75,000 houses in 2022 to a shortage of 390,000 in total). On the other hand: stricter rules on gas emissions that are causing one (new construction) project after another to come to a halt. 

A spin-off from Eindhoven University of Technology (TU/e) is working hard on a solution. That solution comes in the form of 3DCP. "With this technology, we can build faster and improve construction quality. Moreover, the process becomes cheaper and more sustainable because we can use the material more efficiently," ceo and co-founder Zeeshan Ahmed of the tech start-up explained toIO last year.

A lot has happened in the past year. Positive test results were achieved with the two 3DCP systems Zavhy developed, the start-up closed deals with new partners and introduced an alternative binder for concrete. Reason enough to catch up with Zeeshan and R&D engineer Taco Westerouen van Meeteren.
 

RED and FRED

The idea for Zavhy came about when Zeeshan, during his PhD at Eindhoven University of Technology (TU/e), investigated how to overcome the two major limitations of 3DCP technology - the lack of both steel reinforcement (which provides strength) and additives (which improve the properties of concrete).

His research resulted in two revolutionary 3DCP systems: RED and FRED - (Fibre) Reinforcement Entrainment Device. Whereas last year it was unclear whether (F)RED could add sufficient tensile strength to printed concrete structures and whether applying the technology would bring enough cost benefit, those two obstacles have now been overcome.

"We have proven that we can implement structural steel fibers, coarse aggregates as well as reinforcement in the form of steel cables in 3D printed concrete. We have increased the tensile strength of the printed structure from eight to nine MPa to eighteen to twenty MPa*. Moreover, tests show that the cost of our printed concrete can be reduced by twenty to thirty percent by adding coarse aggregates*," says Zeeshan.  The RED system has been used to strengthen both the 3DCP bridge in Gemert (the world's first reinforced 3DCP bridge) and the bicycle bridge in Nijmegen, among others.

A major advantage of the 3D concrete that Zavhy is developing is that no external formwork is needed, but the reinforcement is incorporated internally into the concrete. "Where normally you need very complicated formwork to make sophisticated forms, now you can just add material where it is needed. This ensures that we need much less material," Van Meeteren explains.

Substantially reduced CO2 emissions

The start-up also achieved promising results in the area of sustainability. The company managed to reduce the use of cement 75 percent compared to commercial 3DCP mixtures. By using alternative binders in the printing concrete, the CO2 footprint was reduced from 400 to 100 kilograms of CO2 per cubic meter. Says Zeeshan, "Moreover, the binder we use is derived from recycled waste from the metal industry. Large-scale application of our technology can make a big crucial contribution to making construction more sustainable."

"Large-scale application of our technology can make a big crucial contribution to making construction more sustainable."

CEO and co-founder Zeeshan Ahmed

Hardware and software, construction projects and a 3DCP facility

The young company is working with their consortium partners to create a total solution for the construction industry to drive the growth of the 3DCP market. Zavhy is focusing on developing new 3DCP hardware and software technology, contributing to the realization of 3DCP construction projects and eventually setting up a 3DCP production facility where structures and designs can be printed.Ultimately, Zeeshan wants to franchise its system, to support the Dutch government's goals of building one million homes by 2030. By 2025, at least 10 other 3DCP franchises should be working with Zavhy's system.

"Partly due to our promising research results, in addition to Van Beek and TBRM ES, eight new companies have joined our consortium. Those companies range from multinationals such as Bekaert and Yaskawa to local, Dutch construction companies - Dekker Groep, Remmits GWW, Remix Droge Mortel BV and IMd Raadgevende Ingenieurs - and innovative TU/e start-ups such as AGMAH and Qugate. We see this as an important milestone in attracting industry to work together on a 3DCP solution for the construction industry. We have a common goal: to develop a vision for sustainable, affordable housing and infrastructure in the Netherlands," Zeeshan said.

"We have a common goal: to develop a vision for sustainable, affordable housing and infrastructure in the Netherlands."

CEO and co-founder Zeeshan Ahmed

Finally, the financial support the consortium received from the Dutch government through the REACT EU, MIT R&D and TTT (Thematic Technology Transfer) grants was vital to the creation of the consortium and the industrialization of 3DCP technology.

The entrepreneur stresses the importance of companies from different fields within 3DCP technology - design and construction, robotics and material engineering - joining the consortium. "Only if the technology developed within one domain is compatible with technology from the other domains can we apply 3DCP technology. We are currently working on developing a new bridge project. This will be an upgrade of previous 3DCP bridges in Nijmegen and Gemert with respect to improving strength, durability, cost and environmental impact. And, most importantly: providing a solution for improving automation and digitization in the construction of such infrastructure projects."

<sub>* MPa: megapascal. Pascal is the SI unit for pressure.
* Concrete consists of cement and water, aggregates are used as filler.</sub>