Tunneling operation exposes the adjacent buildings to extra stresses by causing vibrations, ground displacements, and heaves which make these structures in a critical mode. For this reason, researchers dedicate to studying settlement trough due to the tunneling process. Many methods were being proposed to estimate ground surface deformations due to tunneling such as empirical methods, analytical methods, and numerical methods. Most of empirical methods don’t take into consideration the effect of varying densities in cohesionless soil on the surface settlement due to tunneling. A few studies cure this shortage such as Mazek (2014). A proposed equation for assessment of the settlement trough width (i) is to be suggested to calculate the ground surface displacement due to tunneling in different densities of cohesionless soil. The purpose of this paper is to present a comparison between different empirical methods based on surface displacement equation (SDE) due to tunneling. To ensure reliability, a case history along the Greater Cairo Metro tunnel is considered. A comparison between the field measurements, the proposed equation and those obtained by different SDEs is presented. The results show the more appropriate method which approaches the field measurements. Another comparison between the surface displacements calculated by the proposed equation and calculated by Mazek (2014) in different cases in sand soil densities to assessment the proposed equation. The comparison shows a good agreement in results to favor the use of the proposed equation to predict the trough width (i) for variant cohesionless soil conditions.
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