Soft Ground to Hard Rock – Versatile Tunnelling Methods in Urban Areas

Synopsis:

The implementation of modern tunneling techniques in urban areas provides a way to expand infrastructure with little disturbance to the surface and existing structures. When tunneling through hard rock, pre-support measures are not often required. However, pre-support measures, such as ground freezing, jet-grouting, systematic pipe arch canopies, and grouted spiling, are essential to soft ground tunneling at shallow depths. The projects described in this paper show that conventional tunneling can be applied in different urban settings safely, for example in London’s soft ground or New York City’s hard rock.

Zagreb Underground: Proceedings of the Symposium on Underground Solutions in Cities in South-East Europe
March 27-28, 2014, Zagreb, Croatia