TDM tüneli kazısı oluşan oturmalar ve gerçekleşen saha okumalarıyla karşılaştırılması

The Marmaray Project is a modern fast rail-track transportation scheme of 76.3 km connecting the European and Asian sides of the Istanbul City underneath the Bosphorus at a depth of 60 m. The objective of the Project is to establish a transportation capacity for about 150.000 passengers per hour in both directions and to reduce the present total travelling time of 185 minutes by nearly half. In Marmaray project, the tunnels were driven by one Earth Pressure Balance (EPB) and four Slurry Tunnel Boring Machine (TBM) under a shallow cover. The tunelling process induces surface settlements that can cause damage to underground utilities and foundations and buildings and/or disrupt daily life damaging roads and pavements. Because of that reason, the sensetive settlement analysis should be made to take protective and precautionary measure in order to prevent the damages to built environment. Estimation of ground settlement caused by the tunnel excavation is important engineering point. Although there are a large number of sources or causes of settlement, they can be conveniently lumped into two broad categories: those caused by ground water depression and those caused by lost ground. In literature, three methods are exist to estimate the settlements caused by tunnelling, Emprical Method, Analytical Solutions and Numerical Method. Each of these methods are widely used. Precision of the predicted settlements becomes a very crucial issue for urban tunneling in case of a vulnerable built environment. The diversity of the involved parameters particularly under complex and heterogeneous soil matrix may intricate the prediction process. With good modeling of the conditions, the numerical calculations provided much more reliable results compared empiricial methods.