Sustainable shotcrete mix-designs for tunnels with longer service-life

The use of shotcrete is one of the most important support measures in tunnel construction. ASSpC - TU Graz By Christoph Pelzl - A project jointly initiated by the Austrian Society for Construction Technology (ÖBV), TU Graz and OTH Regensburg provides a more systematic understanding of shotcrete applications and forms the basis for new, even more durable concrete mixes and thus for more durable tunnels. The service life of tunnels today is designed to last at least for one hundred years - in the case of the Brenner basis tunnel it is even 200 years. The problem with this: "The service life is currently calculated on the basis of theoretical key figures and empirical values. Environmental conditions such as chemically aggressive groundwater, for example, can possibly lead to cost-intensive maintenance measures earlier than expected," says Florian Mittermayr, researcher at the Institute of Technology and Testing of Construction Materials at Graz University of Technology. Focus on new, fundamental knowledge about shotcrete. One of the most important support measures in tunnel construction is the use of shotcrete, also known as sprayed concrete.