Abstract: The end improvement of the shielded tunnel excavation is an important procedure in the initial and arrival of the shielded tunnel. For the tunnel excavation in rounded gravel soils, there are some special aspects of this technology are discussed. The case history of slurry wall combined with sleeve valve pipe grout method to improve the end of the shielded tunnel is presented in this paper.

Key words: End Improvement, Rounded Gravel Soils, Improvement Zone, Soil Strength, Permeability