| "Lightweight embankment is a type of earthwork using lightweight soil. As the embankment is lighter than ordinary soil, it can be constructed under severe ground conditions, such as on soft ground and steep slopes.In this paper, two kinds of lightweight soil are introduced: air-form mixed stabilized soil and expanded-beads mixed lightweight soil. The air-form mixed stabilized soil is produced by mixing soil, cement agent, air-form and water, whereas the expanded-beads mixed lightweight soil is produced by mixing soil, cement agent and expanded-beads. These soils have a higher density than ultra-lightweight soil such as EPS, but the density can be made lighter than that of ordinary soil by the mixing ratio of air-from or expanded beads.These soils can be used for various purposes such as embankments on soft ground or steep slopes, filling up abutments or pipes. Especially, with a lightweight embankment, earth pressure on soft ground can be controlled and settlement can be reduced. The air-form mixed stabilized soil has been used at six construction sites with a total volume of 19000?, and the expanded-beads mixed lightweight soil has been used at more then 70 sites with a total volume of 70000? by the end of June 2004.Moreover, these soils can be made from excess soil from construction sites. Soil carried out from construction site in Japan totaled 250 million m3 on 2002, yet only 30% of this was reused at other construction sites. Thus, techniques for reusing excess soil are urgently needed." |
