Experimental Results of the Effect of Silica Fume on Grout Injection in Umbrella Arch Method, Case Study: Tehran Metro Line 4

Document Type : Research Paper

Authors

Department of Civil Engineering, Faculty of Engineering, Arak University, Arak, Iran

Abstract

The most important problem in shallow tunnels excavated in soft ground of the urban areas is the surface settlement and its effect on the adjacent structures and facilities of the city, depending on the effects of the range of surface settlement profiles. This feature is clearly visible in Bimeh Station (A4-2) Line 4 of Tehran Metro. One method of supporting tunnel in this circumstance is using the umbrella arch method such as a pre-supporting. Due to the small radius and volume of grout injected into the umbrella arch method and manner of its implementation in field, a homogeneous area containing slurry and soil can be build up around the tunnel. To conduct laboratory studies, soil sampling and in-situ soil characteristics is used to achieve sample preparation. Shear and compressive strength tests were carried out according to the ASTM standards. The shear strength parameters of the soil samples (containing various percentages of silica in the slurry) were determined. The results are presented in tables and figures.

Keywords