Abstract: The aim of this research is to make clear the influence of intermittent vacuum loading pattern on the effectiveness of vacuum preloading treatment of dredged mud with high moisture content. We conducted indoor model tests by changing the intermittence and discussed the mechanism of intermittent vacuum in treating dredged mud. Compared with traditional constant vacuum loading method, intermittent vacuum can reduce the migration of soil particles and improve the transfer efficiency of vacuum in soil, thus improving the reinforcement effect. The dredged mud used in this study is best treated by vacuum loading with intervals of 6 hours. Compared with that of traditional vacuum preloading method, the cumulative water yield of dredged mud by the present method increases by 26.8%, shear strength of cross plate increases by 36.7%, and water content of soil reduces by 18.9%. Intermittent vacuum preloading method is more effective in treating dredged slurry with high water content.

Key words: dredged slurry, intermittent vacuum preloading, model test, water yield, drainage plate clogging