2013 Volume 69 Issue 1 Pages 58-69
Drinking water sludge discharged during water purification contains a lot of organic matter. The generation process of drinking water sludge is quite different from that of general soils, so the influence of organic matter decomposition on the engineering properties is not interpreted enough. Therefore, it is important to investigate the decomposition characteristics of organic matter of drinking water sludge, and to discuss the relation between the organic matter decomposition and shear strength. First, this study isolated fulvic acid and humic acid, and observed the organic matter decomposition and soil respirations. The humic acid content of drinking water sludge was relatively high, and 44% of humic acid was decomposed during 6 month in aerobic condition. Second, triaxial compression tests were executed using the sludge that organic matter has been decomposed by hydroperoxide solutions. Approximately 1.38% of organic matter decomposition showed decrease in the internal friction angle from 39.7°-40.4° to around 37.9°.
