The Effect of Some Engineering Properties of Rocks on Stress Distribution around the Proposed Sheikh Ibrahim Tunnel -SouthJazirah Irrigation Project- Northern Iraq

Abstract

This paper tackles engineering properties of rocks and stress distribution around the assumed tunnel at the proposed site of the Sheikh Ibrahim Tunnel, South Jazirah Irrigation Project, North of Iraq. A full description has been obtained depending on available records, that taken from the executed soil investigation reports of the project. The investigations were done in two stages: the first was the field investigation and the second was the laboratory. The rock mass in Sheikh Ibrahim tunnel mainly consists of evaporite, carbonate, and clastic rocks (marl, sandstone and claystone). Engineering properties have been determined and evaluated through (13) boreholes as previously mentioned in the records and then to establish the preliminary design of the tunnel. The data of (129) rock samples, that conclude laboratory testing (mechanical, dynamical, physical) and field testing ( study of fractures and permeability test), have been used in stress and distribution analysis around the assumed 10 meters diameter tunnel by using the two dimensional finite element analysis program.