Abstract
The Kuroboku soil has particular physical and engineering characteristics compared with ordinary soils. The purpose of this study is to clarify the mechanism of compaction on the Kuroboku soil by investigating soil moisture contained in the compacted soil, and how the organic matter contained in the Kuroboku soil of Daisen & Sanbesan influences the soil compacted effects the value of optimum moisture content, Wopt and maximum dry density, γdmax
The results obtained are as follows:
(1) The compaction curves in drying and wetting processes showed remarkable difference from each other, Particularly, the curves in wetting process were different according to various stages of initial water content. This result carne from the effect of soil moisture which had over pF 3. 5 in the compacted soil on working of apparent soil particles.
(2) The pF value of Wopt shown in both of the wetting and re-drying processes was approximately 3.0.
(3) The relation between Wopt and γdmax in Daisen and Sanbesan soils was respectively linear and. the same with common soil reported so far.
(4) The Wopt value of Daisen soil was larger in comparison with that of the Sanbesan soil. On the other hand, the γdmax value was contrary.
(5) The value of Wopt or γdmax of Kuroboku soil was found to be closely related to the organic matter content of soil, and the correlation between Wopt and organic matter content was positive, and the correlation between γdmax and organic matter content was negative.
