Ground Movements due to Soft Ground Tunneling

Abstract: The prediction and mitigation of damage caused by construction-induced ground movements represents a major factor in the design of tunnels. This is especially important for shallow tunnels in congested urban environments, where expensive remedial measures such as compensation grouting or structural underpinning must be considered prior to construction. The goal of this research is to develop and evaluate new methods for predicting ground response due to tunneling. Research supported by Ferrovial-Agroman simulates Earth Pressure Balance (EBP) tunnel boring machines in clay. The analyses consider the role of face pressure, grouting around the precast lining rings and complex (non-linear and inelastic) properties of the surrounding soil. Site-specific predictions have been compared with recent field measurements during construction of Crossrail tunnels in London and with results of simplified analytical models. Research is now focused on interactions of the tunnels with overlying buildings.