Slurry improvement by vacuum pre-loading in combination with electro-osmosis and with dynamic compaction method

Abstract

Aiming at the problem of serious soil cracking during electro-osmosis stage in the treatment of dredged slurry by vacuum pre-loading in combination with electro-osmosis method, this study proposes a new vacuum pre-loading method in combination with electro-osmosis and with dynamic compaction to overcome these drawbacks. Meanwhile, different current ratios are used to characterise the different activation times of the dynamic compaction to achieve the optimal activation time. Five laboratory tests were performed on dredged slurry in self-made plexiglass model bucket, and the electric current, drainage of soil, soil surface settlement and vane shear strength, etc. in the reinforcement of dredged were monitored. The test results show that the combined action of the vacuum pre-loading, electro-osmosis, and dynamic compaction process enhances the circuit current, improves the efficiency of the electro-osmotic drainage, and thus promotes the drainage of the soil and ultimately yields a better reinforcement effect. Meanwhile, the dynamic compaction process effectively reduces the energy consumption in the process of vacuum pre-loading combined with electro-osmosis. In addition, the optimal effect owing to the dredged slurry can be evoked when the dynamic compaction is activated in the middle stage of the electro-osmosis process.