Recap of the SCHWENK Concrete Seminars 2024

For many years, it has been a good tradition to kick off the new construction season with the SCHWENK Concrete Seminars. Unfortunately, in recent years the customer event could not always take place at the beginning of the year due to COVID. We were therefore all the more pleased to be able to hold the 2024 Concrete Seminars again in January as usual.

This year, a total of around 750 participants accepted the invitation to the events held by SCHWENK Zement GmbH & Co. KG at the three locations Schweinfurt, Leipzig, and Heidenheim.

The in-person events organized by SCHWENK Bauberatung are a fixed part of the calendar for customers, concrete manufacturers, construction companies, government representatives, architecture and engineering firms, as well as university representatives. They all took the opportunity of this industry gathering to learn about current topics related to the building materials cement and concrete, and to exchange ideas in person.

This year’s events focused primarily on clinker-reduced cements and resource efficiency. These are the key challenges facing cement and concrete manufacturers now and in the future.

Mr. Werner Rothenbacher, Head of SCHWENK Bauberatung, guided the participants through the seminar program and moderated the discussions as usual. He expressed his delight that once again so many participants had attended the Concrete Seminars.

Dr. rer. nat. Hendrik Möller, a member of the executive board of SCHWENK Zement GmbH & Co. KG, welcomed the participants and delivered the first presentation, “Pathways to Climate Neutrality.” He explained that the greatest challenge at present is achieving climate neutrality within the specified timeframe while simultaneously meeting high investment requirements. At SCHWENK, we are working in parallel on various solution strategies to achieve the statutory goal. In addition, we plan to radically reduce the clinker factor in cement and to capture, store, or utilize the CO2 generated during the process.

To achieve this, a research and development facility of the CI4C consortium is being built in Mergelstetten to test the so-called “Pure Oxyfuel process.” Furthermore, at SCHWENK we are focusing on the market introduction of novel, innovative binders. Celitement will play an important role in this regard. However, finding an adequate replacement for the quantities of blast furnace slag and coal fly ash as supplementary cementitious materials that will be phased out in the coming years is also a particular challenge. To address this, a pilot plant is now being built at the Allmendingen site to fill this gap using clays and natural pozzolans. Dr. Möller concluded by emphasizing: “SCHWENK is prepared for the future!”

Construction consultants Dipl.-Ing. Heiko Zimmermann in Heidenheim and M.Sc. Christian Fratscher in Schweinfurt and Leipzig presented on the topic “Clinker-Reduced Cements—Opportunities and Challenges.” Two clinker-reduced cements are already established in ready-mix concrete and thus contribute to a lower carbon footprint in concrete. The use of these cements is particularly advantageous for CSC environmental certification. The speakers anticipate that demand for certified concrete will rise in the future, especially in metropolitan areas. It is advantageous that all SCHWENK cement plants hold the CSC “Gold” rating and that eco-friendly cement variants—in some cases even in bagged form—are available at every plant. The transition to new cement types in the precast concrete industry poses a particular challenge, as early strength and demolding strength determine productivity at the plants. Experience with various customers has shown that combining CEM I with a clinker-reduced cement (CEM II/B-M, CEM II/C-M, CEM III) can be a way to reduce the carbon footprint while maintaining production cycles. Additionally, optimizing the mix design by adjusting the water-cement ratio or adding setting accelerators can be effective. SCHWENK Construction Consulting would be happy to advise you on this matter.

Dipl.-Ing. Sven Mellwitz gave a presentation in Leipzig on the new concrete standard DIN 1045, while Dipl.-Ing. Kai Fischer spoke on the same topic in Heidenheim and Schweinfurt. Participants received information on the new DIN 1045-1000:2023-08 “Fundamentals and Concrete Quality Classes (BBQ).” This standard categorizes the complexity of construction projects into different concrete quality classes and defines the interfaces between planning, concrete production, and construction execution. To strengthen the necessary communication, the intensity of BBQ-N (normal requirements), BBQ-E (increased requirements), and BBQ-S (requirements to be specifically defined) is being increased. Planning and construction are also guided by this tiered system. The classification of concrete construction quality depends largely on the structure’s intended use, the applicable exposure classes, strengths, and construction methods/curing. Exemplary classifications provided participants with clarity on the system. In addition, new features and changes in DIN 1045-2:2023-08 “Concrete” were presented. Important DAfStb guidelines were incorporated, and the use of recycled aggregates was made easier. The permissible admixture quantities were increased in some cases, and the use of recycled aggregates is permitted under certain criteria. Furthermore, clinker-reduced cements were incorporated into the standard, and changes to the conformity assessment were implemented. The building authorities are expected to introduce the complete set of standards around the turn of the year 2024/2025.

In addition to climate change, improved resource efficiency in the construction industry is also becoming increasingly important. In his presentation titled “Resource Efficiency as a Building Block for Sustainable Construction,” Dipl.-Ing. Werner Rothenbacher, Head of Construction Consulting, discussed ways to conserve mineral resources. This primarily includes the use of recycled aggregates in concrete or as raw materials or additives in cement production. Cement and concrete account for about one-fifth of the total 1.2 billion metric tons of primary raw materials extracted in Germany. Only a holistic approach leads to success, which includes not only recycling but also the reuse of building structures and entire building components. The VDZ Roadmap provides a good overview of the quantities that can be replaced in the future. Finally, the successful practical implementation of the circular economy in the “Mercedes-Benz Arena Renovation” project was presented in detail.

Using well-founded data and facts on “Concrete 4.0,” scientists from the Institute for Building Materials at Leibniz University Hannover—Dr.-Ing. Max Coenen in Schweinfurt and Prof. Dr.-Ing. Michael Haist in Leipzig and Heidenheim—demonstrated how artificial intelligence can be used for quality assurance in concrete production. By using digital images—such as spread tests—and sensor data, it is possible to make predictions about expected building material properties within a trained AI environment. The speakers presented the fundamentals of this approach and shared promising examples from both laboratory and practical applications.

During the subsequent lunch, all participants had the opportunity to refresh themselves and discuss the technical presentations with each other or with the speakers.

The afternoon at the Concrete Seminars is dedicated to the well-known speakers and experts who present interesting topics beyond the building materials cement and concrete.

In Schweinfurt, internet crime expert Cem Karakaya from Munich entertained the audience with his anecdotes and expertise on the topic “What do James Bond and Cybercriminals have in common?” In a humorous way, he demonstrated how each individual handles personal data on the internet and social media, and how criminals can exploit this knowledge.

Business psychologist Dr. Carl Naughton from Wiesbaden demonstrated in his presentation in Leipzig how “courage for the future can serve as food for thought.” The focus of his talk was on the human capacity for mental adaptability to change, and he provided valuable insights into helpful coping strategies in both professional and personal life.

Back in 2022, neuroscientist Prof. Dr. med. Volker Busch from Regensburg already fascinated participants in Leipzig with his presentation on “Brain Under Pressure.” This year, the presentation was also very well received in Heidenheim. A look inside the brain reveals ways to deal intelligently with information overload, multitasking, and the digital everyday life. He provided tips and tricks on how each individual can escape the spiral.

We are already looking forward to next year’s seminars, which are expected to take place on the following dates and at the following locations:

• Thursday, January 23, 2025 in Heidenheim
• Tuesday, January 28, 2025 in Schweinfurt
• Thursday, January 30, 2025 in Leipzig