A concrete answer for circular construction: three prototypes reusing saw-cut elements

Existing concrete buildings should be retained for as long as possible to reduce the environmental burden of demolition and new construction. However, when urban pressure makes demolition unavoidable, salvaging and reusing concrete elements elsewhere in new structures, rather than reducing them to rubble, efficiently prolongs the use of existing resources at their highest structural value. Concrete reuse is not a new approach: pioneer cases have demonstrated its potential, but broader adoption has still not been seen across the wider industry. Three prototypes recently built by Ecole Polytechnique Fédérale de Lausanne researchers and students in Switzerland demonstrate the feasibility and potential of reusing elements saw-cut from cast in situ concrete structures. The prototypes deal with different scales of elements, from small blocks to large slab elements and 3D assemblies. Lifecycle assessments confirm that reusing concrete elements drastically reduces the upfront global warming potential of new construction, providing a new lower-bound benchmark for sustainable, circular construction.