Towards net-zero infrastructure: fixing clay with clay

Research Project, 2022 – 2024

Creating new, upgrading or maintaining existing infrastructure for higher traffic loads and/or stricter alignment, as needed for realising the transport plans in Sweden, is difficult in areas with soft clays, found in the urban areas near the coast. A challenge is to accomplish all this with net-zero emissions, and yet in a robust manner, at an acceptable societal cost. Currently, soft clays are seen as inferior materials, with little value as raw materials, as well as expensive and risky to build on. This project overcomes these limitations by Enabling net-zero infrastructure with novel clay-based
binders for sustainable ground improvement; fixing clay with clay. An unique combination of expertise on geomechanics and building materials science are brought together to create lime-cement-calcined clay and natural clay (LCCNC) mixtures with a
minimum amount of CO2-eq, and yet controllable geomechanical response.
Experimental and numerical modelling techniques will be combined to ascertain the repeatability, scalability and practical applicability of the methods developed reducing the amounts of lime and cement that have a heavy carbon footprint. The novel binders will enable sustainable material use in ground engineering by starting from the natural clay. This not only reduces the emitted CO2-eq, but it will also reduce wastage and increases value in the supply chain. As such, it will become an enabler for net-zero infrastructure on soft soil areas in Sweden and abroad.