Experimental study on ionic soil stabilizer combined with vacuum preloading to solidify sludge

Combined reinforcement methods have increasingly become the trend for ultra-soft soil foundation treatment with super high-water content and a large amount of floating mud. Based on the vacuum-aided grouting technique and principle of vacuum preloading soft foundation reinforcement, an efficient in situ sludge solidification technology ionic soil stabilizer (ISS) combined with a vacuum preloading device to improve the mechanical properties of sludge and effectively avoid secondary pollution from sludge is proposed and verify it through laboratory test. Based on the vacuum-assisted grouting technology and the principle of vacuum preloading soft foundation reinforcement, the sludge solidification technology of negative pressure (vacuum) combined with ISS is studied. The physical and mechanical property indexes, soil settlement, drainage, etc. are analyzed before and after the sludge solidification to establish the potential of the vacuum preloading-assisted grouting technology and ionic solidification process. The experimental results showed that ISS combined with vacuum preloading has better curing efficiency and curing effect than vacuum preloading alone. Under the combined action of ISS, the surface settlement and drainage volumes of sludge treated by the vacuum preloading method increased by 26.46% and 78.54%, respectively, and the water content of the solidified sludge greatly decreased. Under the action of vacuum preloading, ISS injection made the soil easier to compact, decreased pore volume, and improved the compressive strength of the sludge.