Original Paper(Vol.59 No.1 pp.50-55)

Repairing Material for Embankment Using a Bottom Sludge of Age-Old Reservoir

Kenichi SATO, Takuro FUJIKAWA, Hiroyuki TANAKA and Suehiko YOKOTA

Abstract: At the moment, there are 210,000 reservoirs in Japan, and 70% of them have already aged more than 100 years. Consequently, it becomes serious problems such as the decline of usable capacity due to deterioration, declining quality of reservoir water, and alluvial bottom sludge. Therefore, it is imperative that the improvement of reservoirs. Especially, bottom sludge is difficult to transport to outside of reservoir because it has high water content and high organic matter. Since it becomes difficult to secure the landfill recently. Bottom sludge is really required to utilize effectively on site. In this research, ancillary material is utilized to decrease water content from bottom sludge and the development of repairing material for embankment has attempted. In this research, blast-furnace type B and stabilized soil with cements which is effective to the highly organic soft clay were utilized as a solidification material. Then, plaster powder (milled plaster board), paper sludge ash and bamboo powder (milled bamboo) were used as an ancillary material. In order to develop a new repairing material for embankment, unconfined compression test and cone index test were carried out. As a result, it was revealed that the additive rate of solidification material for required strength could be decreased effectively by using above-mentioned ancillary materials.

Key Words:Bottom sludge, Unconfined compression test, Cone index test, Solidification treatment, Plaster powder, Paper sludge ash, Bamboo powder