World Tunnel Congress 1997 on Tunnels for People / 23rd General Assembly of the International-Tunnelling-Association on Rock Characterisation for Tunnelling, Vienna, Austria, 12 - 17 April 1997, pp.455-460
The population of Istanbul, Turkey's biggest metropolitan area, the most important historical city and commercial center, has increased in the last two decades to more than a 10 million. Its ancient character and historical monuments severely restrict the construction of wide roads, consequently municipal authorities planned to solve the transportation problem in the city by starting the construction of 16 km, two lines metro at the end of 1992. This paper summaries first, Istanbul Metro project, construction method, the geology of the area and physical and mechanical properties of the rock formation. All the shift data were collected carefully during the construction of the tunnels by the shift engineers of the contractor. The data was analyzed statistically as a main objective of NATO TU-Excavation Project and the cutting performance of two road headers, ALPINE ATM 75 and EICKHOFF ET 250 used in Taksim line were compared with the performance of Jack Hammers, the main part of the conventional drivage technique used in most of the Istanbul Metro Tunnels. Rock mass properties were correlated with the performance of different mechanical excavators and general conclusion was drawn for further efficient applications.