Abstract
The bulk density values were examined for mixtures in which swine manure was mixed with sawdust, rice husks, and returned swine manure compost as supplementary materials. The mass per unit area and the bulk density up to a deposition height of 2 m were estimated from initial bulk density and the regression equation of the settlement rate of the load test using a small vessel. The initial bulk densities of the mixtures were lower in the saw dust mixture and higher in the returned compost mixture than in previous studies. The amount of subsidence was larger when the moisture content was higher in the sawdust mixture, however the relationship with the moisture content was unclear in the rice husk mixture and the returned compost mixture, and the difference due to the supplementary materials was also small. The obtained bulk density values were about 60 to 70 % for the rice husk mixture, 80 to 90 % for the rice husk mixture, and 110 to 120 % for the returned compost mixture than the previous values. These differences were caused by the different dry mass ratios of swine manure and supplementary materials and the different properties of the supplementary materials, so the influence of the changes in the properties of swine manure was considered to be small.
