2020 Volume 76 Issue 4 Pages 394-404
The Modified GIN method which arranged the mix proportion of the grouting material, the injected pressure and the amount of the injected grouting material and considered as the safety and the quality assurance has been developed and employed at a construction site. In order to evaluate the grouting performance through Modified GIN method, in this research, CT images of borehole core samples are taken through both medical X ray CT and μ-focus X ray CT and are analyzed. Based on the CT images, it is confirmed that the grouting material are filled into the aperture of fracture. In the wide aperture, it is also confirmed that the filling grouting material consists of some layers. In the actual construction, the low density grouting material was injected in the first step, and then the high density grouting material was injected if the proposed injected pressure was not arrived in the first step. It is thought, therefore, that the CT images show the good agreement with the actual construction process.