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Interview with the new Scientific Director of 4TU.Bouw

Monday, 22 June 2020

Maarten Hornikx (TU/e) has been the Scientific Director at the 4TU.Bouw Center for Built Environment since February 2020. He has taken over the role from André Dorée (UT) who will continue his involvement in the centre as one of the four TU ambassadors.

The 4TU.Federation interviewed Maarten about his first impressions, the future of the construction sector and about his own field of research, the influence of sound on the built environment.

For anybody not familiar with 4TU.Bouw, what does it do and what is its strength?
4TU.Bouw is an alliance between the building faculties of the four universities of technology, Delft, Eindhoven, Twente and Wageningen.
Our primary aim is to develop an agenda to achieve innovations in architecture, engineering and construction (AEC) sector as part of the entire chain of innovation, from research at universities to completed buildings. At the individual faculties, we have been working on this for quite some time. But when all of the 4 TUs join forces, that makes you a lot stronger.
4TU.Bouw also has an important advisory role. It provides a single point of contact for questions from the AEC sector. For example, if you need an expert on the nitrogen problem, we will come up with some names and that person doesn’t need to go to each separate university. It is a really quick way of mobilising the support you need.
As building faculties, we also combine forces in joint research programmes. Having the expertise of four universities increases your chance of securing funding and achieving academic success.
Finally, the building faculties join forces to provide the joint 4TU Master’s degree programme in Construction Management & Engineering. This integrated programme combines the different areas of expertise that the building faculties offer. As 4TU.Bouw, we work closely together to deliver engineers who not only have the necessary construction and engineering skills but also the ability to oversee complex innovation processes. These are the kinds of engineers needed to effectively address the complex, multidisciplinary issues in construction and wider society.

“Materials and processes will need to become circular. If the construction sector is to play a meaningful role in this, it will need to come up with innovative solutions. If you fail to do that, you will always be behind the times.”
Maarten Hornikx

You mentioned innovation in the AEC sector – why is it so important?

The AEC sector does not innovate quickly because it is a relatively archaic sector in which much of the work is still done manually. At 4TU.Bouw, our aim is to raise awareness in the sector of the need for innovation, provide inspiration through good examples and ensure that the knowledge and expertise we develop at the universities actually find their way into the construction process. 

I would also emphasise that this is not innovation for innovation's sake. You engage in innovation because of issues in society. For example, we aim to achieve a circular society by 2050. This will have an impact on construction. Materials and processes will need to become circular. If the construction sector is to play a meaningful role in this, it will need to come up with innovative solutions. If you fail to do that, you will always be behind the times.

Are there any other reasons to innovate?
Yes, it will make the construction sector less vulnerable. Currently, activities in construction are very dependent on economic trends. If there is a downturn in the economy, it is reflected in construction. In my view, if there is a lot of innovation in a sector, it makes you less dependent on the economy. Predictions are already being made about how the world of construction will be hit hard by this period.

How do you see the future of construction and architecture?
An important area where a concerted effort is required in the sector is digitisation. A lot of the work in construction that is currently done manually could be automated. As well as being more efficient, this gives you greater control over processes and the digital overview makes it easier to coordinate different parts of the work.
Let me give you an example. In the future, it is envisaged that houses will be 3D printed. You already have semi manufactured houses that are made in the factory and finished at the building site. But it may soon be possible to print a whole house. In Eindhoven, we have a concrete printer that can print almost any shape you want. This not only breaks with the tradition of straight walls, but also calls for a different production chain. As well as requiring fewer hands, this technology also offers added flexibility.

The digitisation of construction is one of the items on the agenda for the BTIC Building and Technology Innovation Centre. The centre brings together all of the sectors in construction: the ministries, the knowledge institutions and the building federations. Henk Visscher (TU Delft) represents 4TU.Bouw in it and focuses on innovation and the R&D component.
It has just launched a series of three Knowledge and Innovation programmes, including the Digitisation Knowledge and Innovation Programme. These programmes have been agreed across the whole of the construction industry. There is now a long-term strategic vision for digitisation in construction (including robotics, artificial intelligence, virtual, augmented and mixed reality and digital twins).

“I see 4TU.Bouw as the watchdog for R&D and technological innovations like 3D printing and virtual reality. They require structural investment in order to safeguard the future of our sector.”

The BTIC aims to be a platform for achieving innovation across-the-board in the construction sector. Because its work focuses on themes – these include energy transition and circularity alongside digitisation – it is making real progress in terms of innovation. Personally, I see our role in this forum as the watchdog for R&D and technological innovations like 3D printing. For the future of our sector, it is important to ensure there are structural investments in these areas and also to provide funding for doctoral candidates, for example, to guarantee the continuity of academic lines of research.

You mentioned 3D printing as an important innovation, but you probably also have other examples?
Yes of course. I also see virtual reality (VR) as a promising innovation. For example, it could be applied to construction at neighbourhood level, where VR can be used to enable citizens to experience and see how their area will change and involve them in the choices being made. When you are installing a layer of asphalt or a noise barrier, for example, you can allow people to experience the difference in exposure. This helps create public support because you are using VR as a means of communication.
But you can also use VR as a digital twin. This enables you to virtually monitor the entire construction process by means of a digital copy and discuss progress with the people you are working with in the chain. In that case, VR is a way of making work processes more efficient.

Are there any other themes that you feel should be addressed?
Personally, I think that the way universities work could be improved. Traditionally, the work of universities is based on disciplines whereas most issues in construction are thematic. Take a topical theme like the energy transition. If you want to put forward effective solutions in that area, you need several disciplines that can all contribute their knowledge and innovation. On the one hand, you have the energy-generation mechanisms and sources and, on the other, integration within the built environment and a certain degree of public acceptance.
In the academic world as it is now, collaboration is still under-appreciated. In my view, there is still too much focus on the university disciplines and individual academics’ performance in that context.

I want to see 4TU.Bouw putting this issue more in the spotlight. In the future, I would like to see universities appoint people who excel in a particular theme and the associated disciplines can then rally behind them, operating in an integrated way. That will enable you to bridge the gap between problems in society and the different areas of expertise within universities even more effectively. Indeed, that is also one of the strengths of a federation like 4TU.

That brings us to my next question: what do you see as 4TU’s greatest strength?
The most important thing for me is for a researcher to contribute to resolving an issue in society. If you can do that with others, that brings nothing but advantages. You secure more funding, gain more knowledge and have greater impact. When you want to highlight the importance of social problems related to our sector and secure more government funding to address them, you are unlikely to succeed as a single university on your own. That is another area where joining forces makes much more sense.

Finally, can you tell us something about your background?
My field is acoustics – the science of sound. I focus on the influence of the built environment on sound. In a concert hall, for example. How does this environment affect the sound? Or an aircraft. How does sound travel through air, through the different layers of air in the atmosphere?
My role involves gaining new knowledge on the one hand and providing solutions on the other. Concert halls, like lecture halls and canteens, must be well designed. That calls for effective solutions in terms of materials, but also in the communication process. You need to get people on board – they have to be able to picture it for themselves. You can use calculation models for this, but the best way is to listen. Acoustics is a specialist language. If I say to someone ‘the souns is 60 dB here’, it has very little meaning for most people. But if you can allow something to be heard – for example in VR – they have a better impression of it. VR is also very effective in studies of experience and perception. I really enjoy the physics component and the perception component in this kind of research, and the combination of the two. In fact, 4TU.Bouw is the perfect place for me, because I can switch between different areas of knowledge. That is why I can’t wait for all the partnerships and alliances I expect to see launched in my new role as director of research!

4TU.Bouw is a cooperation of the building departments of the universities of technologies in the Netherlands (Delft, Eindhoven, Twente, Wageningen). More information you can find here.

Professor Maarten Hornikx is professor of Building Acoustics, vice-dean of the Faculty of Architecture and the Built Environment and head of the chair in Building Acoustics in the department of Building Physics and Services (BPS). Hornikx’s expertise is in modelling sound in the built environment.
Maarten Hornikx gained an MSc at TU/e (2004) and a doctorate in applied acoustics at Chalmers University of Technology (2009). He began his career there as a senior researcher working on EU-funded projects, in which he focused on models charting the distribution of urban noise.
He has been awarded two personal Marie-Curie grants: a Marie-Curie post-doc scholarship (2009) and a Career Integration Grant (2012). Currently, he is coordinating an NWO OTP project and the H2020 ITN project Acoutect. Hornikx also collaborates closely with various industrial partners in the field of virtual acoustics and sound-absorbing materials.