injection and vent openings

As part of the SNAM Mestre–Trieste pipeline project, Future Foundations successfully carried out the grouting works following the installation of a 16-inch (406 mm) gas pipeline within a series of bored tunnels. The tunnels, with diameters ranging from 1.2 m to 1.8 m and lengths of up to 1,670 m, required the annular space between the pipeline and the tunnel wall to be completely filled to ensure the long-term stability and protection of the installed infrastructure.

To achieve a homogeneous and continuous fill, a dedicated grouting system was implemented using a bentonite-cement mixture. The tunnels were equipped with strategically positioned injection and venting points, allowing the grout to be placed in a controlled manner while preventing air entrapment and ensuring complete filling of all voids along the entire tunnel alignment.

Through careful planning, continuous monitoring and precise execution, approximately 6,600 m³ of grout was injected, providing optimal support and protection for the pipeline. The successful completion of these works demonstrates Denys’ expertise in delivering specialised grouting solutions for complex underground infrastructure and energy projects.