Long term behavior of two component back-fill grout mix used in full face mechanized tunneling

In mechanized tunneling the annular gap between the segmental lining and the surrounding soil caused by tunnel driving, must be backfilled almost instantaneously with an adequate grouting mortar when tunnelling in soils and particularly in urban area at low overburden. The main goal of this research is to investigate the grouting performance of two-component grout mix also when long curing time is considered.