玉野 富雄

Participating in a construction work on a very soft clay ground, the authors had to know the availability of the slurry-trench method in the clay ground. Therefore, they excavated three trial trenches to see the cases of unstable, critical and stable conditions of the trenches in the clay. Based on these trenches and investigation of clay at excavated places, they found that the stability of slurry-trench in the clay ground could be judged with the degree of consolidation of clay. The clay ground of overconsolidation ratio equal to or greater than 1.0 can support a slurry-trench stably. This judgement was checked and discussed with a slurry-trench in another site measuring the deformation and the pore-water pressure of clay ground.