One of the main issues involved during tunnel construction with tunnel boring machines is the tail gap grouting. This gap is between the external diameter of tunnel lining and the excavation boundary that is filled with high-pressure grouting materials. In this work, three different approaches of gap grouting modeling in the FLAC3D software are investigated with a special attention to the...

tunnelling through cities underlain by soft soil, commonly associated with soil movement around the tunnels and subsequent surface settlement. the predication of ground movement during the tunnelling and optimum support pressure could be based on analytical, empirical or the numerical methods. the commonly used earth pressure balance (epb) tunneling machines, uses the excavated soil in a pressu...

Tunnelling through cities underlain by soft soil, commonly associated with soil movement around the tunnels and subsequent surface settlement. The predication of ground movement during the tunnelling and optimum support pressure could be based on analytical, empirical or the numerical methods. The commonly used Earth pressure balance (EPB) tunneling machines, uses the excavated soil in a pressu...

In the tunnelling industry, a large share of market is occupied by EPB (Earth Pressure Balance) machines. To operate this kind machine, radical change in rheological behaviour excavated soil must be performed, and achieved adding water, foam, and, eventually, polymers. The stability foam assessed through half-life test. main limitation test that only one value used characterization degradation ...

ground settlement is often the most serious concern when tunneling under an old city with numerous historic monuments. a successful engineering design under these conditions would require getting the most out of the ground strength parameters and avoiding any weakening maneuver throughout the operation. knowing that surface settlement is highly affected by tunneling parameters in epb shield tun...

The visualization system of soil fluidity in the chamber EPB (Earth Pressure Balanced) shield has been developed to maintain appropriate excavated real time during advance under tunnel construction. For further improvement system, agitation tests fluid admixed with foam have carried out study relationship between number rotations and agitating torque soil. It is confirmed by that sand reduces i...