DEVELOPMENT OF A SPRAYABLE GEOPOLYMER CONCRETE FOR FIRE PROTECTION IMPROVEMENT AND UPGRADING OF UNDERGROUND TRAFFIC STRUCTURES

摘要

The existing tunnel structures in Germany are characterised by progressive ageing, which is particularly evident in the tunnels' inner lining. In addition, under the influence of incisive events and new research results over several years, the government has reviewed and updated some of the guidelines under which these buildings were designed and constructed. If this deterioration now requires the repair of a building, the new requirements must be taken into account. This can sometimes lead to a considerable increase in the requirements for operational safety, durability, resistance, or structural fire protection. In the German research project KOINOR, a sprayable geopolymer is being developed which should fulfil the requirements for a tunnel lining of the new guidelines. The focus here is on high fire resistance as well as high resistance to other concrete-attacking substances, such as chlorides or sulphates. This publication presents the first results on the applicability of a sprayable geopolymer concrete. Therefore, investigations of the geopolymer application process and its fire loading material properties are now being discussed. First fire tests are also hinting towards a substantial fire resistance and no spalling issues with this new material at all, which could help with a lot of current problems of traffic tunnels in general and road tunnels in special.