Demolition of Pavilion building: new step in research into circular concrete

The Pavilion is the oldest building on the TU/e campus (year of construction 1956). Its demolition is in full swing. The demolition is taking place with great respect and policy and is part of a European study into circular concrete. Among other things, the aim is to reuse the precast concrete beams and columns from this building.

TU/e researchers are looking at ways to improve demolition, dismantling and reuse during the demolition process. In doing so, they aim to optimise the design process of new buildings for reuse, in order to build more sustainably.

The Pavilion is one of four demonstration projects of the international Horizon-2020 programme 'ReCreate'. TU/e Faculty of Built Environment, TU/e Department of Real Estate, engineering firm IMd and floor manufacturer Consolis-VBI are carrying out the Dutch demonstration project.

The European Commission has allocated €12.5 million to the overall project. Of this, 2.3 million will go to TU/e for the appointment of three PhD researchers, a project manager and the realisation of the Dutch demonstration project. Other projects are in Finland, Sweden and Germany. There, researchers are specifically looking at quality assurance, logistics, climate impact, marketing and knowledge transfer.

Rijk Blok, project leader of the Dutch partners and researcher at TU Eindhoven: "Cement production releases a lot of CO2. Moreover, the large quantity of sand and gravel needed has a considerable environmental impact. So if we want to make construction more sustainable, concrete is an important material to scrutinise."

He continues: "In doing so, you want to reuse the materials at the highest possible level. So not grind them into granules first. If we want to use less fossil materials, we really need to start looking at improving reuse."

And that is not so easy. Older buildings have no hallmarks that tell the quality of the concrete. The rebar that was the norm 40 years ago may no longer pass the latest requirements. In addition, the elements may be damaged when dismantled. This could also further reduce the quality. In doing so, the municipality obviously wants to have black and white proof that it meets all the requirements. Blok: "Constructive safety is and remains an absolute requirement, of course."

And imagine that the quality was perfect: a concrete column that carried one storey in the old building cannot suddenly handle more storeys in the new building, of course. Blok: "So precisely in the design process of a new building, you should actually already take into account the elements you have available for reuse."

And then there are the higher costs you incur, for example for careful dismantling and storage . So the cost-benefit analysis does not necessarily fall in favour. Blok: "New cement is simply cheaper at the moment. But it might not be in the future, for instance with the import ring of a climate tax or higher CO2 tax on concrete." Still, Blok remains optimistic: "Problems are there to be overcome. If we want to become more sustainable, we need to research the framework conditions precisely now."

Photo: TU Eindhoven