Geotechnical zoning of tunnel excavation site of tunnel 'Višnjica'

Geotehničko zoniranje tunelskog iskopa tunela 'Višnjica'

Abstract

  Tunnel 'Višnjica' is a part of collector 'Interceptor Ušće - Veliko Selo' that is going to be the main Belgrade municipal sewerage system. Twentyone inquiry borings (1,254 m of boring) were performed on tunnel route and representatives for laboratory investigation were separated from them. Laboratory investigation was aimed at getting parameters that would enable distinguishing of geotechnical categories on distinctly heterogenous terrain. In order to define geotechnical conditions for building construction, geotechnical zoning of terrain in the area of excavation site was performed. It was performed according to lithological structure of distinguished lithological complexes, thickness of upper layer, resistant-deformable properties of distinct environments and the possibility of water occurrence at excavation site. Based on distinguished geotechnical areas and their characteristics, geotechnical categorisation of excavation site into four categories was done. All categories were appropriate for hydro-shield method application.