Prediction of Induced Settlements by Conventional Tunneling in Urban Area
This paper aims to share the lessons learned from the conventional excavation induced settlements in the Metro project of Üsküdar – Ümraniye – Çekmeköy (UUC) in Istanbul. The ongoing UUC project intended to extend the metro network at Istanbul Asian side. Starting from the recently opened Marmaray railway link in Üsküdar, the metro stretch runs 17 km underneath a high dense urban area, whereof 8 km of tunnels are being excavated using conventional methods through weak to medium strong sedimentary rocks. Due to the project spatial extension, conventional excavation induced settlements are being systematically predicted using the semi empirical Gaussian curve approach. The computed settlements basin is compared with accurate FEM analyses at critical sections and back analysis from actual monitoring data, bringing to successful approach in weak rock excavation with a significant gain in prediction speed.