Abstract

Due to rapid urban population growth and spatial constraints, the demand for designing and constructing high-rise buildings has significantly increased. This trend has led to deeper excavations and a greater need for effective stabilization methods. The present study investigates the performance of various stabilization techniques—including soil nailing, prestressed anchors (anchorage), and their combination—under static conditions, with a focus on deep excavation stability. Numerical modeling was conducted using FLAC3D software. Five static models incorporating different stabilization systems were designed, considering geotechnical soil properties, excavation dimensions, and static loading. The numerical analyses evaluated safety factors, wall displacements, and axial forces in retaining elements. Additionally, the effect of applying shotcrete was assessed across the models.

Results indicated that using soil nailing alone without shotcrete surface coverage does not provide adequate stability for deep excavations and may lead to wall failure in certain cases. Improved soil cohesion and the application of shotcrete significantly enhanced model performance. Among the static models, the anchorage system with shotcrete (Model 4) demonstrated superior performance, achieving a safety factor of 2 and minimal displacement.

In conclusion, selecting an appropriate stabilization method based on geotechnical conditions, soil cohesion, seismicity of the region, and shotcrete implementation plays a critical role in ensuring the safety and stability of deep excavations.