Use of the DSI Hollow Bar System for the Stabilization of Vijenac Tunnel

A new motorway is currently under construction that is designed to improve the infrastructure between Bosnia and Herzegovina as well as Croatia. The project forms part of the 5c Pan-European Transport Corridor and is an important prerequisite for ensuring the positive economic development of the whole region.

Construction work on the motorway also included the new 2.9km long Vijenac Tunnel in Bosnia. Work on the double tube highway tunnel began in July 2011, and completion is scheduled for the beginning of 2014. Tunnel advance was carried out in accordance with the New Austrian Tunneling Method.

DSI Austria supplied the complete range of important ground control products for tunnel driving. This also included Type R32 and R38 DSI Hollow Bar Rock Bolts including accessories as well as grout pumps. The DSI Hollow Bar System proved itself by fulfilling the following technical characteristics in this project:

• Simultaneous drilling and grouting ensures an optimum bond between the hollow bar tendon and the unconsolidated rock or ground
• The construction soil is improved by the infiltration of the grout into the surrounding unconsolidated soil
• Uniform distribution of the grout along the complete installation length

The advantages of the DSI Hollow Bar System had already convinced the client in comparable projects. Principal advantages include the fast and safe self-drilling installation process as well as the possibility to drill, install and grout in a single operation using standard drilling equipment.

Once again, the client was very satisfied with the products that were supplied for this project as well as with the comprehensive services offered by DSI Austria and the technical support provided by experienced DSI employees on site.