Croatia

AT-Pipe Umbrella Support System allows safe Driving of Omis Tunnel

The most important route between the Croatian seaports of Split and Makarska is the D8 National Road. This road was built very near to the shoreline of the Adriatic Sea in the 1960s. Today, the road finds itself in the middle of numerous towns which have grown in the last decades. Due to continuously increasing traffic volume, the government decided to expand this coast road and to construct spacious bypasses for several towns.

A critical part of this infrastructure upgrade project was the construction of a 1,471 m long tunnel as part of the bypass of the town of Omis, some 25 km south of Split.

Due to the comparatively small depth of cover at the tunnel location, it was necessary to start with a pipe umbrella support at the portal. DSI supplied its reliable Type 114 mm AT-Pipe Umbrella Support System, which provided the protection and safety for the first tunnel driving work. Tunneling was carried out mechanically using excavators and shotcrete in accordance with the New Austrian Tunnelling Method (NATM). For further tunnelling works, DSI supplied DYWI® Drill Hollow Bar Self-Drilling Anchors in lengths of 3,000 mm each to secure the heading face. However, the geology encountered often required short-term recalculations of the necessary anchoring forces. Hence, different types of DYWI® Drill Hollow Bars were used. The Hollow Bar System is designed for differing rock mass conditions: The DYWI® Drill Hollow Bar drill bit design and diameter can be easily and flexibly adjusted. Various types maintain the basic dimensioning of the required anchoring forces. Eventually, necessary functional adjustments of the required anchor lengths can be carried out easily using the appropriate couplers.

The opening of the new Omis bypass tunnel is scheduled for the end of 2012.

x

Related articles:

Issue 06/2009 Construction Equipment

Australia’s longest Road Tunnel in Brisbane

The city of Brisbane on the East Coast of Australia is Queensland’s industrial, economic and financial center. Many service companies are located in the city center. Brisbane Central Business...

more
Issue 03/2021 DSI Underground

Efficient Use of Forepoling Technology at the Arlinger Tunnel

The 1.35 km long Arlinger Tunnel is part of the first construction phase of the “Westtangente Pforzheim”, the connecting axis of the German federal roads 294 and 463 from the Black Forest to the...

more
Issue 01/2019 Avesco | Sandvik

Dry Excavation with modified Tunnelling Jumbo

Description of Project Since 2014, a railway tunnel with two single-track tubes with lengths of 2449 and 2426 m has been under production starting from Stuttgart-Nord. The tunnel for its part is an...

more
Issue 03/2021 India

Extreme Working Conditions: The Rohtang Road Tunnel in the Indian Himalayas

The 8.9 km long, single-tube two-lane tunnel was built to avoid the dangerous route over the Rohtang Pass at 4000 m above sea level. The new link shortens the Manali–Leh Highway by about 50 km and...

more
India

Extreme Working Conditions: The Rohtang Road Tunnel in the Indian Himalayas

The 8.9 km long, single-tube two-lane tunnel was built to avoid the dangerous route over the Rohtang Pass at 4000 m above sea level. The new link shortens the Manali–Leh Highway by about 50 km and...

more