The Dugi Rat tunnel is situated along the D8 State Road, spanning from JUNCTION “TTTS” to JUNCTION “DUGI RAT” and OMIŠ. This tunnel will comprise two tubes: the primary (traffic) tunnel tube, measuring 852.46 meters in length, will accommodate two-way traffic with a single lane per direction. The second tunnel tube, extending 540.2 meters, will serve as an evacuation tunnel designed for passenger evacuation in case of incidents. To facilitate connectivity between the tunnel tubes, three cross passages for pedestrians will be incorporated.

CTP PROJEKT has been contracted to prepare the Elaborate and Presentation of fire protection measures, the ventilation system, and the fire alarm and fire protection for the tunnel.

In the design of the ventilation system for the Dugi Rat tunnel, distinguished by a steep longitudinal gradient of 4%, the project team rigorously adhered to elevated safety standards and guidelines. A pivotal aspect of this process was the application of Swiss guidelines, particularly ASTRA 13002, addressing the ventilation of safety corridors (galleries) in road tunnels. The significance of these guidelines is evident in the incorporation of overpressure ventilation in evacuation tunnels, serving as a critical component for passenger safety. Additionally, ASTRA 13004, focusing on fire detection in road tunnels, played a crucial role in the design by implementing an early fire detection system.