Challenges and Innovations in Deep Excavation in Urban Areas: Integrated Design and Construction Practices

Abstract

The rapid pace of urbanization and demand for high-rise developments have intensified the need for deep excavations to accommodate underground infrastructure. Executing such projects in dense urban areas is challenging due to complex soil–structure interactions, limited space, nearby lifelines, and strict deformation control requirements. Conventional support-of-excavation (SOE) systems often fall short under these conditions. This paper presents an integrated design and construction methodology combining field data, numerical modeling, and real-time monitoring to address these challenges. Case studies from Tehran with excavation depths of 19.5–43 m highlight key innovations in soil nail wall systems and hybrid shoring. A major finding is that post-construction deformations, often underestimated, can rise by 69–222% beyond initial values, exceeding standard guidelines. Incorporating a Load Relaxation Factor (LRF) into PLAXIS 2D analysis improves prediction accuracy, while AI-assisted monitoring and adaptive design enable safer, more economical, and sustainable deep excavation solutions in complex urban settings.