An evaluation of fine grained sedimentary materials in terms of geotechnical parameters which define and control excavation performance of EPB TBM’s

Abstract

Abstract Studies have been conducted on Istanbul-Buyukcekmece Waste Water Tunnel route in order to determine the influence of plastic behavior and adhesion potential of fine grained clayey sedimentary soils as well as the lump form effect on the EPB-TBM’s excavation performance. This research was designed to develop data modelling methodology for a risk assessment of excavating in form of lumps, the adhesion problem on the metal surfaces, and clogging. Back analysis was carried out by linking advance rate (mm/min) data with geotechnical properties of the excavation material. The influence of water and other conditioning chemicals in different proportions on the plasticity index and consistency index of the material was also investigated. In this research, material samples from 14 different points between 1285 and 2186 m of Buyukcekmece Waste Water Tunnel (6.09 km in total length and 20–40 m in depth) that was being excavated in sedimentary clayey materials of Gurpinar formation with an EPB-TBM (O = 3.45 m excavation diameter) were evaluated.