Numerical modelling for optimizing shoring wall performance in deep urban excavations

Abstract

Soil nailing and anchoring are effective methods for reinforcing the soil in situ, providing internal support that enables the earth to sustain itself during and after excavation. To ensure optimal performance, it is essential to monitor the behavior of the soil nail walls throughout the excavation and after completion, so that the SOE system design can be improved. This study presents a comprehensive survey of the design and performance of soil nail walls in deep urban excavations at depths ranging from 19.5 to 29.3 m. After construction, the lateral deformations of the soil nail walls varied significantly from 69% to 222% of the initial deformations observed immediately after completion. Numerical analyses were used in the design process to accurately predict the wall performance and determine the design characteristics to identify appropriate design parameters and predict the wall behavior. Several numerical models using different modelling approaches are examined, and the results demonstrated that post-construction deformation rates can vary between walls based on factors such as the soil nail and anchor system design and geotechnical conditions at the excavation site. A thorough understanding of these variables is crucial for optimizing the performance of SOE systems in deep urban excavations.