Numerical modeling is considered a useful tool for the evaluation and quantitative
interpretation of field data for assessing the original design or construction method. In this
paper, numerical modeling is used to investigate the optimum construction method for a
tunnel proposal to underpass the railway tracks at Elhosania crossing in Zagazig city,
Egypt. A relatively short length is suggested here to be constructed by the NATM (New
Austrian Tunneling Method) instead of the traditional cut and cover method. This is the
first time that the application of NATM in considered in Egypt. The purpose of the
numerical simulation is to analyze both methods to determine the deformations and
stresses in the tunnel vicinity and to check tunnel stability and the suitability of the
construction method. Additionally, the way of strengthening the ground to ensure higher
safety for NATM has been investigated using numerical modeling. The numerical results
are promising; they help to minimize the construction cost and also help the decision
makers to choose the optimum solution for other tunnels and other lines in the future. |
