Congress „The future of concrete“ by Holcim company hosted at ETH Zurich.
- Interesting discussions on a strong increase in recycled beton/concrete: pretty soon concrete will contain a mandatory percentage of recycled content. Structurally and aesthetically there is no disadvantage, but the advantage is less virgin material (i.e. cement) and of generate on-site less transportation traffic.
- Foamed concrete and on-site foaming techniques lead to decreasing transportation weight and traffic of cement and further ingredients to the construction site.
- Fiber-concrete allows for lighter and stronger constructions, again decreasing transportation traffic.
These are all potentially positive developments in making the concrete building sector more eco-efficient!
What we really need to ask, though, goes beyond the „efficiency“ discussion towards „effect„: how can be drastically change the way we construct buildings and look at the whole system, including grey embodied energy, material and energy flows, and cradle-to-cradle?! Then we may think about cement-free constructions, lighter and more flexible, using renewable building materials like wood. If the use of concrete is technically needed, there are more ecologically friendly types of cement – such as Prompt from Vicat/Grenoble – and there are organic fibers from renewable resources (like industrial hemp) to create different types of fiber-concrete without using carbon fibers.
At the MonViso Institute we use both Prompt binder/cement with a lower embodied grey energy due to a lower burning temperature and no substitutes, and hemp fibers for the most environmentally friendly fiber-concrete in lowest amounts possible as stripe foundation.