Ground Response due to Buried Structure Construction Process

Document Type : Original Article

Authors

1 Syrian Air Forces, Syria.

2 Egyptian Armed Forces, Egypt.

Abstract

Deep aircraft shelter and deep fortification are major projects of buried structures in military purposes. The Greater Cairo metro and El-Azhar road tunnels have been constructed as major projects of buried structures in Cairo City. Deep fortification construction causes movements in surrounding soil. Ground movement is an important factor during buried structure construction. Buried structure construction in cohesionless soil is a sophisticated process leading to cause potential damage to exist surface and subsurface fortification structures. Ground movements depend on soil properties, buried structure depth, buried structure diameters, and method of construction. In this study, the finite element analysis (FEA) is used to predict surface displacement due to buried structure process based on case study. Surface displacement equation (SDE) proposed by Peck and Schmidt (1969) is also used to calculate surface displacement due to buried
structure construction process. For assessing the reliability of the FEA, a case history along the Greater Cairo Metro tunnel Line 2 is considered. A comparison between the field measurements and those obtained by the FEA and the SDE is made. The surface ground movements obtained by the SDE are examined with those obtained by the FEA at different sand soil densities. However, the SDE does not consider impact of different sand soil types. The surface settlement profile computed by the SDE is in poor agreement with those obtained by the FEA in loose to medium sandy soil. The surface settlement profiles computed by the SDE agree well with those calculated by the FEA in dense and very dense sandy soil. Finally,
the finite element analysis is a good tool to analyze different sandy soil densities at which different sand soil stress and strength parameters are considered in the FEA.

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