Experimental investigation on electro-osmosis-surcharge preloading-chemical grouting for silty soft soils

Soft soils with high water content, high compressibility and salt content, low permeability and shear strength, significant structural and rheological properties are widely distributed in Jiangsu Province. The treatment of these soft soils is complicated, therefore, the traditional methods cannot effectively consolidate the soft soils. To improve the consolidation efficiently, electro-osmosis is combined with preloading and chemical grouting to develop a new approach, electro-osmosis-surcharge preloading-chemical grouting. Laboratory tests are conducted on several soil samples to evaluate the effectiveness of the combined method. The water drainage, effective potential, vane shear strength as well as the ultimate water content are examined. The results indicate that the combined method results in the increase of heap load, which inhibits the generation of cracks and effectively improves the loss of the electric potential. The contact between electrode and soil is also increased to effectively utilize the combined effects of the electro-osmosis, chemical grouting and surcharge preloading. Moreover, the combined method of electro-osmosis-surcharge preloading-chemical grouting can promote the electro-osmotic drainage, and reduce the trend of low drainage rate with an increasing duration for the consolidation process.