Stockholm Southern Link (Södra Länken)

The Southern Link is a 6-km, mostly underground motorway that forms the southern quadrant of the prospective Stockholm Inner Orbital Expressway. Constructed though suburbs close to the city center, it includes twin 3.8 km through-tunnels, each with 2 unidirectional traffic lanes, expanding to 4 lanes at various branch points. Together with 3 shorter tunnels, all entries, exits and the original access tunnels, the Southern Link project involved about 17 km of urban tunneling. This required over 2 million m3 of rock to be excavated sensitively by drill-and-blast, which presented engineers with some extremely interesting challenges. As for many tunnels in Sweden today, full pregrouting of the tunnels was mandatory, even in zones of hard and competent rock, in order to avoid undue disturbance of the groundwater table. With a construction cost of SEK 7.9 billion (USD 1.13 billion), the Southern Link Expressway opened to traffic in October 2004.

 

Nitro Consult was appointed Construction Manager (Rock Works) in the HT consortium. We were also commissioned to carry out structural surveys, determine vibration limits and then measure, monitor and report vibration and noise.