The construction and infrastructure sector consumes half of all raw materials in our country and accounts for 40 percent of energy consumption and a third of total CO2 emissions. Because half of all building materials are concrete, a lot can be gained by making it more sustainable. TNO has developed a new approach and tool for this.
“TNO will present the approach to more sustainable concrete on 14 June 2022 on Concrete Day”
Switch to more sustainable concrete
This TNO approach focuses in particular on the use of more sustainable types of concrete and the recycling of secondary raw materials. Until now, these materials have not yet been used on a large scale, primarily because use in concrete structures is complex. On the one hand, there is a change in the concrete, as we have always known, and on the other hand, there are more and more requirements, a construction must not only be safe and affordable, but also sustainable and circular.
The new approach, in its entirety ‘Material-driven Multi-criteria Design Optimization’ (MIMO), is a design approach to more sustainable concrete that helps make optimal choices for several parties involved: customers, construction companies, contractors, demolition companies, recycling companies.
The MIMO approach (pdf) forms a hub between data, models and smart optimization software. Information on locally available raw materials is central: ‘resource-based technology’. For example, the material properties of elements or grains from concrete rubble are determined, the data. In addition, all requirements are set at the same time, such as minimizing environmental impact and costs, but also maximizing safety because we want safe concrete structures.
MIMO then processes the data using calculation models for design scenarios that optimally and measurably meet the different requirements at the same time. The user can now easily consider what the best case scenario is based on wishes and planning.
(Read more below the picture.)
Every year, about 22 million tons of rocky waste are released through demolition. Currently, only 2 million tonnes of this is recycled, while we produce 33 million new concrete each year. TNO assesses that MIMO can support assessment and optimal utilization of recycling and recycling from construction and demolition waste.
“This flow accounts for more than half of current concrete production!” says Siska Valcke from TNO, an expert in circular concrete. “When optimizing recycling, also for CO2 reduction, thanks to MIMO, two important strategies will soon emerge: full recycling of elements from existing concrete structures and the use of crushed rubble will be estimated at 0.75 to 1.25. million tonnes of CO2 reduction per year, ”explains Valcke.
Optimal use of information
MIMO is in line with initiatives that the sector is already developing, such as new concrete types with less cement, slimmer construction and removable construction. The parties can balance and optimally combine different strategies for sustainability and circularity.
The new approach is now being tested on a limited scale as a tool. This demonstrates the benefits of the approach for the parties involved if it is used at different stages of decision making and design. Designers can, at an early stage, incorporate the capabilities and data of suppliers, demolition companies and recycling companies into their design in order to arrive at an optimal solution.
Customers gain insight into solutions that measurably meet their requirements and that they can compare transparently with each other. Contractors and demolition companies gain measurable insight into the costs and benefits of smart disassembly and storage of materials.
Lays the foundation for more sustainable concrete
MIMO is set up in such a way that new design questions, requirements, data and models can be added and linked together, so that it can be implemented more step by step.
Siska Valcke: “Our approach provides the greatest value when cooperation in the concrete sector grows: companies, governments and knowledge institutions. Then MIMO can be an enabler in the chain-wide transition to more sustainable concrete. The foundation has been laid, and from here we can start working with the sector to make the transition to large-scale resource-based technology on the road to more sustainable concrete. ”
More TNO information
TNO presents the MIMO approach on 14 June 2022 on Concrete Day.