Cairo metro network is one of the major national projects in Egypt. It aimed at
developing underground transportation system to solve the severe traffic problems in
Greater Cairo which includes 3 crowded governorates; Cairo, Giza and Qalyubia. The
project started in the last decades of the twentieth century where 2 lines were
executed. In this century, the project is expanding and more lines are constructed. The
tunnel constructed for Cairo Metro Line 3 has a circular cross section that consists of
a precast segmental lining thickness of 0.40 m. This paper presents a parametric study
on the effects of seismic waves on the tunnel structure through numerous simulations
employing the finite – element analysis. Full dynamic analyses were performed
employing three different earthquake motions as well as the effect of train-induced
dynamic load. Also, the induced tunnel straining actions were studied. The analysis
of soil-structure interaction was done using the commercial software PLAXIS®. The
results proved that the 0.40 m thick circular cross section can safely sustain the
expected static, dynamic and seismic stresses. |