Tunneling is an important engineering project that interacts in a complex manner with the surrounding geology. This interaction can significantly influence the choice of the tunnel layout, excavation technique, and reinforcement/consolidation strategies.
Information able to anticipate problems related to the choice of the excavation techniques, water inflows, the future behavior of utilized materials, and hence the cost of the infrastructure, are then fundamental.
It is possible that the excavation in a tunneling project alters the geological conditions of a site.
Tunnels often have a draining function, they may induce settlements in the above ground. In particular accidental inflows of water bearing non-choesive ground into the tunnel can provoke surface subsidence. In hard ground blasting in shallow tunnels may cause damage to buildings at surface.
Historical InSAR data provided by Fragile Srl can be used to characterize the natural displacement field in the area of interest before the tunnel construction, and effectively address the layout planning of the infrastructure.
Areal InSAR analyses can be also very useful to investigate the surrounding of the site to fully understand the geological and geomorphological context. A summary knowledge of the site and the surrounding could comport, for instance, a tunneling-induced reactivation of a dormant landslide body.
InSAR based displacement data supplied by Fragile can be useful InSAR can also be used during the construction stage of the infrastructure when monitoring the evolution of tunneling induced displacements is crucial. InSAR-based displacement data will be continuously reinterpreted in the geological context of the area to better understand what lies ahead.
InSAR analyses provide important information also after the conclusion of the construction phase for management purposes. Fragile Srl offers InSAR based near real-time monitoring to assess geological features like landslides or subsidence and their effect on the existing structure.