ABSTRACT
The increasing population in metropolitan areas requires a concomitant upgrade of the infrastructure. The majority of the infrastructure is subterranean, especially in congested urban areas. Due to the preexisting structures on the surface, the construction of new projects is subject to specific restrictions such as subsidence and/or noise limitations during construction. In urban areas, the ground generally consists of sedimentary soil and/or highly weathered rock mass. Both types of ground are prone to major displacements during tunneling. These settlements control the entire design process due to the project limitations, as compliance with the design requirements may demand additional support systems including ground freezing, jet grouted columns or pipe jacking, which are time and cost intensive.
