Homogeneity of self-compacting concretes used in tunnel strengthening – A case study

This work presents the results of an experimental study carried out to evaluate the homogeneity of the self-compacting concrete (SCC) used for the strengthening of the Montblanc tunnels, in Spain. These tunnels are part of the new high-speed railway line Madrid–Zaragoza–Barcelona–French border, partly under construction. The experimental program involved non- and semi-destructive techniques; georadar scanning combined with the extraction and laboratory testing of core samples. The results indicate that the great filling ability capacity of SCC allows obtaining an adequate material homogeneity in this type of applications, characterised by very high reinforcement ratios and difficult casting conditions.