Client:                     
FFG: TIKS - Technologien und Innovationen für die klimaneutrale Stadt

Project management:
Architekt DI Thomas Matthias Romm - forschen planen bauen ZT

Cooperation partners:
CarStorCon Technologies GmbH
Doka GmbH
Dr. Ronald Mischek ZT GmbH
Holcim (Österreich) GmbH
Materialprüfanstalt Hartl GmbH
Strabag Real Estate GmbH
Transportbeton Gesellschaft m.b.H. & Co. Komm. Ges.
Wopfinger Transportbeton GmbH

Processing period: 2019-2024

Concrete and cement production are of considerable environmental relevance; at the same time, concrete is by far the most widely used building material worldwide. Austria has an annual cement consumption of 5.2 million tons and emits approximately 2.9 million tons of CO2 per year for its production (MAUSCHITZ, 2020, p. 7, 7a). Decarbonization of the construction industry is a global issue. The present project is intended to make a contribution to this.

The research objective is the use of "performance concrete" as CO2-reduced concrete (RCC - "reduced carbon concrete") with a lower cement content. In contrast to conventional concretes, the technical equivalence has to be proven by the technical properties ("performance"). The basis, in addition to ÖNORM B 4710-1, is the future ONR 23339 "Rules for the implementation of the concept of equivalent concrete performance". This standard will set the framework, how to compensate the delayed early strength development of RCC concrete by suitable curing measures at the construction site.

Findings:
Clinker-reduced concrete mixtures have lower CO2 emissions than standard concretes. The delayed early strength development of CO2-reduced concrete - reduced carbon concrete (RCC) - due to the lower binder content poses a challenge, particularly at low outside temperatures. This lack of energy at the beginning of the hardening phase can be compensated for by a.o. heatable formwork. Yet heating the formwork with electricity does consume energy, further contributing to CO2 emissions. Therefore, the life cycle assessment of heatable formwork to support CO2-reduced concretes is key to evaluating the sustainability of innovative RCC formulations. The following research question can be addressed as follows: How can the life cycle assessment of heatable formwork to support CO2-reduced concretes be evaluated and to what extent does this influence the sustainability of innovative concrete mix designs?

Prospects:
The results of the research series and the addition of technical carbon create important prospects for the industry-wide use of CO2-reduced and climate-neutral concrete. This means the possibility of establishing climate protection goals with performance concrete in accordance to ONR 23339 as the new state of the art without a minimum binder content.

Publications:
RCC-Reduced Carbon Concrete - Implementierung von CO2-reduzierten Betonen auf der Baustelle

Die Ziele des vorliegenden Projekts „RCC – Reduced Carbon Concrete“ war es, das aktuelle Wissen um die temperaturabhängigen Aushärtungsverläufe der Performancebetone durch Betonarbeiten an großen Bauteilen auf der Baustelle, unter sommerlichen und winterlichen Bedingungen, sowie in der Fertigteilproduktion zu erproben. Die Ergebnisse fließen in die Baupraxis und die Normungsarbeit ein. Schriftenreihe 30/2021
T. M. Romm, N. Summhammer, T. Belazzi, M. Härtel, J. Horvath, E. Größ, L. Kujawa, R. Hoch, M. Marra, R. Pamminger, M. Löffler, F. Denk, H.-J. Zeiler
Editor: BMK
German, 60 Seiten

https://nachhaltigwirtschaften.at/resources/sdz_pdf/schriftenreihe-2021-30_rcc.pdf

RCC2 – Reduced Carbon Concrete 2: Ökobilanz heizbarer Schalung für CO2-reduzierten und klimaneutralen Beton
Experimentelle Entwicklung innovativer Rezepturen CO2-reduzierten Betons sowie beheizter Schalung zur Unterstützung der Frühfestigkeitsentwicklung bei winterlichen Temperaturen. Schriftenreihe 26/2024
T. M. Romm, J. Flaszynska, M. Härtel, M. Kopp, D. Ehrenreich, T. Meinschad, P. Kasal, T. Belazzi, J. Horvath, M. Schwarzbauer, L. Kujawa, R. Pamminger, M. Löffler, F. Denk, H.-J. Zeiler, J. Hörler, J. Roth, A. Preuß, T. Groeneveld
Herausgeber: BMK
Deutsch, 71 Seiten

https://klimaneutralestadt.at/resources/pdf/schriftenreihe-2024-26-rcc2.pdf