Rehabilitating instead of rebuilding aged or damaged pre-fabricated concrete buildings for reducing CO2 emissions: the case of Ukraine

Recycling the concrete of old and destroyed buildings and using it to build new buildings is a promising technology for post-war Ukraine, but in many cases, it may be economically and environmentally more justified to rehabilitate such buildings. This article provides an analysis of the state of the housing stock of Ukraine from prefabricated reinforced concrete from the point of view of the possibility of its rehabilitation, mainly based on the forecast of the degree of carbonation of different types of concrete structures in various conditions. Based on the results of this analysis, it can be stated that the service life of internal concrete structures can generally be extended up to 100 years, while external concrete elements after 50 years of operation may already require replacement or repair. A comparative analysis of various reconstruction strategies in Ukraine from the point of view of CO2 emissions is also given. It shows that the rehabilitation of such buildings is the most meaningful strategy.