Keywords: closed face TBM, field measurements, nonlinear finite element analysis, primary and secondary lining.

The El-Azhar Road Tunnels consisted of two tunnels of 9.40 meter external diameter, 1700 meters in length, the tunnels will be constructed with a closed face machine and lined with precast segments. The tunnels must be constructed using a Tunnel Boring Machine (TBM) with the closed form face with earth pressure balancing and Bentonite slurry (mix-shield TBM).

The purpose of the present study is to investigate the behavior of El-Azhar Road Tunnels with respect to stress reduction at the face of an excavation. This is important to control ground deformation and excess pore water pressure due to the process of shield tunnelling in three dimension and time-dependent. The excavation stages during the advance of the machine in 3-D consolidation analysis is simulated.

The ability of the method to account for nonlinear material behavior through iterative processes allows the simulation of a realistic material behavior. Meanwhile the ability to divide the excavation process into several loading steps allows the inspection of the various stages of excavation and the observation of stress paths followed by different elements in the soil continuum.

The Quality Control for the tunnel construction is achieved by using different devices for field measurements (horizontal, vertical displacement for the soil and ring deformation).

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