To solve the problem of vast cement and low strength in the treated sludge, clay mineral used for accessorial solidification material was applied to advance strength. The principle of solidification sludge strength because of clay mineral is not clear and has not supported the choice of clay mineral. The mineral and pore water is analyzed in order to contrast clay mineral added or not based on the XRD and pore water chemical character. The result shows that the absorbed quantity of Ca2~ was reduced by sludge because of clay mineral added, the hydrated reaction was advanced and integrated solidified materials was formed.
The fractal model about water characteristics of solidified sediment was built according to the granular metric analysis curve of solidified dredged sediment, the measured value during the low-suction stage of the curing process was used for fitting parameters in the model to obtain the complete water characteristic curve of solidified dredged sediment. Then, the quantitative calculation model of capillary water, attached water, evaporated water and bound water was built by the water characteristic curve and from the view of quantitative angle, the paper analyzed the solidification mechanism of solidified dredged sediment. The result showed that： the model can realize the quantitative calculation about different tapes of water during the curing process, the evaporated water during the curing process mainly came from the capillary water, and the generated bound water during the curing reaction came from the attached water.
