ReSaMon - Sustainable production of sandwich elements for the construction sector

Sandwich elements are increasingly being used in the façades of industrial halls and cold stores. In the ReSaMon project, the BMWK is promoting optimized production of the elements. In the project, a consortium of seven partners is developing a non-destructive and non-contact measurement technology that can identify potential weak points and changes in material properties during the production process. Fraunhofer LBF is investigating the possibilities of data-based methods for detecting and localizing defects in conjunction with the developed measurement technology.

Sandwich elements:

More than 20 million m² of sandwich panels are produced in Germany every year, 200 million in the EU. They consist of two metallic cover layers and a core of PUR or PIR foam. The structure results in a very low mass combined with a high load-bearing capacity, making the elements ideal for lightweight design. This is why they are increasingly being used to close off roofs and walls in building construction, for example on the façades of industrial halls and cold stores. .

Resource-efficient sandwich elements through non-destructive monitoring for lightweight construction

The Federal Ministry for Economic Affairs and Climate Protection (BMWK) is funding a research project to optimize the production of the elements. It is called "Resource-efficient sandwich elements through non-destructive monitoring for lightweight design (ReSaMon)" and runs until the end of September 2024. The aim is to develop a non-destructive and non-contact ultrasound measurement technology that will identify possible defects and changes in material properties in the sandwich elements during the production process, directly afterwards or in the installed state.

Data-based methods for defect detection and localization

In ReSaMon, Fraunhofer LBF is investigating the possibilities of data-based methods for detecting and localizing defects. This is done both simulation-based using a digital twin and in combination with the developed measurement technology. Here, LBF's many years of expertise in the field of vibration technology are combined with efficient simulation methods and machine learning methods for pattern recognition.

At present, defects can be reliably detected in elaborately generated data sets with a detection rate of over 95%. This means that faulty elements can be distinguished very well from faultless ones. The localization of defects also works successfully with detection rates of 76 % and more (see video). The differentiation between defective and defect-free elements based on experimental data will be investigated in the final year of the project.

Improvement in production processes fewer complaints and CO2 emissions

At the end of the project, the sandwich element manufacturer involved will benefit from the improvement in production processes and therefore fewer complaints and CO2 emissions.

Sponsors and partners

Sponsor: Federal Ministry for Economic Affairs and Climate Protection (BMWK)  

Partners:

• Covestro Deutschland AG
• ArcelorMittal Construction Deutschland GmbH
• iS-engineering GmbH
• Inoson GmbH
• Fachgebiet Mess- und Sensortechnik (MuST) der TU Darmstadt
• Fachgebiet Stahlbau (im IFSW) der TU Darmstadt
• Fraunhofer-Institut für Betriebsfestigkeit und Systemzuverlässigkeit LBF