Tunnel boring machine of 2nd Heinenoordtunnel: source of seismic signals

In Netherlands, many tunnels are constructed over the years to cross waterways. Until now, mostly immersed tunnels were built. The 2nd Heinenoordtunnel is the first large diameter tunnel in Netherlands that is bored in soft soil like sand, clay and peat. The tunnel has two tubes which go under the river Oude Maas near Rotterdam through Holocene and Pleistocene layers, Both tubes have a diameter of 8.3 m and are 1350 m in length, of which 950 m is bored. During the tunnel construction work, numerous measuremants and experiments carried out under the coordination of the Centre for Underground Construction (COB in Dutch) to study the use of the Tunnel Boring Machine (TBM) Among these, seismic research was performed by the Subfaculty of Applicd Earth Sciences of the TUDelft.