Professor Danièle Waldmann helped set up the construction and civil engineering department at the University of Luxembourg, and is now working on a research project regarding sustainability in construction.

Science.lu spoke to Waldmann about her work and vision for the future of sustainable building.

What is your main research focus?

As a professor of solid construction, I am head of the Institute for Civil and Environmental Engineering at the University of Luxembourg. In the area of ​​solid construction, my goal, along with seven doctoral students and two post doctorates, is to generate sustainable concrete. We cover the entire range of concrete: concrete, reinforced and pre-stressed concrete and masonry construction.

Have you found this to be a typically male-dominated area?

Yes, solid construction generally is male-dominated. At one point, there were two other female professors in the university's engineering department, but they have since left.

Has that been an obstacle to your career?

No. However, it is structurally more difficult for women to reach the same career level as men at the same time in life, for example due to child-bearing or childcare periods. My gender has never played a role in my daily work, not even on the part of my male colleagues.

RTL

Professor Danièle Waldmann

How do you envision sustainability in construction?

We try to cover the entire life cycle of concrete, so it starts with renewable raw materials that we add to the concrete. We also look at the structure of the building so that it can later be "taken apart" and include monitoring to achieve a long lifespan. At the end of the day there is also the option to recycle buildings. These are all important considerations when you consider that construction alone accounts for 35% of global CO2 emissions. In addition, we try to recycle industrial waste products when producing new concrete, thereby helping to conserve resources.

Can you name specific examples of projects which can achieve greater sustainability?

Aggregates in concrete, such as sand and gravel, for example, can be replaced with renewable raw materials such as Chinese reed or wood chips. We are also investigating other aggregates, as part of an “Interreg” project, where we are looking at how previously unused clay materials, which are incurred as sludge or as a waste product in gravel pits without any further use, can be re-used as an additive. This is very promising, as this material can partly replace the cement and does not require the same high firing temperatures, which then saves energy.

Are you also investigating how concrete could be recycled in Luxembourg?

Yes. Investigating this in detail is particularly relevant for Luxembourg, because the resources here are more limited than elsewhere. We need to know exact details for a number of aspects: How much old concrete is actually used in Luxembourg? To do this, we have created maps and models of the country's cities in order to estimate the built-up volume of building materials and, in particular, the amount of concrete used. This is also very important for our industrial partners, because they naturally want to know whether an investment in recycling is worthwhile. Bringing old concrete over long distances in order to meet the prescribed recycling criteria would be neither economical nor environmentally friendly.