Automated production line for adaptive concrete modules of high-precision

• Subject Area: Construction Engineering and Architecture
• Term: Funded in 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 501824812

The application is for a multi-variable facility to produce highly precise components made of reinforced concrete. The components are individual modules that are assembled on site to form a holistic structure. The facility will be integrated into the KIB-KON testing hall at the Ruhr University in Bochum. The facility is designed to explore fully quality-assured production based on the flow principle and to operate in a largely automated, robot-assisted manner. It covers the processes of automated shuttering and reinforcing, concreting, rapid hardening by controlled heat treatment, geometric and material quality control, as well as sensory equipment and labeling. All consecutive processes are holistically quality-assured and interactively controlled from a digital overall representation (digital twin). High variability in geometries, reinforcements, built-in components, in heating via mats and hot air and in quality assurance with optical, thermal and mechanical processes is important. Research objectives are: Geometric and material precision: The goal is to explore and extend the limits of achievable accuracies. Target requirements are deviations of shuttered surfaces ≪1mm, reinforcement layers <2 mm, component edges relative to each other <1 mm. Concretes must have low scatter in strength throughout (standard deviation <2 MN/m²). Geometric adaptivity and free form: The modules should be similar, not identical, and variable in basic parameters such as lengths, widths, angles, reinforcement or surfaces. They are planar or truss-like and must be able to feature arbitrarily curved surfaces. The concept of the formwork includes adjustable walls and built-in parts to realize curved edges. Metallic or non-metallic reinforcements shall be prefabricated, installed, and welded by robots or connected by clips. Speed in the overall process and intermediate steps: The research aims to minimize the production time of a module to less than 3 hours, including concrete curing. Partial goals aim to develop controlled heat treatment techniques (<2 h) and concretes suitable for these. Sub-processes have to be established in a trade-off of speed, accuracy and achievable load-bearing capacities. Seamless quality assurance: The goal of production is seamless quality control of all relevant geometric, mechanical and process-specific parameters. Well-established "no-fault quality standards" (Six Sigma, i.e. 99.99966% fault-free with DMAIC) of production engineering shall be transferred to prefabrication in the construction industry. Envisaged are optical controlling (laser, photogrammetry), thermal analysis (thermography) and indirect strength tests on fixed terminals or robotic arms. Link to digital overall representation: All manufacturing, quality assurance and labeling processes are to be controlled, monitored and regulated in real time using digital models.

• DFG Programme: Major Research Instrumentation
• Major Instrumentation: Automatisierte Fließfertigungsanlage für adaptive, hochpräzise Betonmodule
• Instrumentation Group: 2300 Baustoffmaschinen
• Applicant Institution: Ruhr-Universität Bochum
• Leader: Professor Dr.-Ing. Peter Mark