Diego Jesus De Souza
Project title: Development of a framework to provide concrete with a low carbon footprint and enhanced durability properties
Host Institution: Technical University of Denmark (DTU)
Host Supervisor: Prof. Dr. Wolfgang Kunther
Co-host Institution: Technical University of Munich (TUM)
Co-host Supervisor: Dr. Anne Heisig
Summary project: The concrete industry needs to find cost-effective technologies to reduce the carbon footprint of its products. At the same time, these technologies should not reduce the concrete’s performance, including long-term durability. For instance, Alkali-Silica-Reaction (ASR) and Internal Sulfate Attack (ISA) are physicochemical deterioration mechanisms initiated by a combination of components of the binder material and aggregates containing unstable silica grain in aggregates (ASR) or aggregates containing sulphides. The demand for concrete and the expected shortages of high-quality aggregates in the coming years will enhance the probability of using inferior raw materials, reducing the lifespan of concrete infrastructures.
This study aims to develop a new “chemical composition mix-design” approach toward mitigating ASR and ISA while reducing the carbon footprint and cost of concrete. This work will test “artificial” blended types of cement mixtures that fall into the “safe” combination of CaO, SiO2, and Al2O3 (main oxides in cementitious materials) for their resistance to expansion and damage development.
To measure this approach’s success, the mixtures’ hydration will be studied to ensure the desired differences in hydrate phases, paired with pore solution, mechanical, and microscopical analyses. Moreover, thermodynamic modelling will allow new insights into the resistance of new cement/binder mixtures concerning ASR and ISA development.
Ideally, this project will provide a framework for developing a mix-design tool that allows engineers to make safe material choices for improved construction materials utilization of new and “lower” quality materials.