Abstract: To investigate the impact of air-booster vacuum preloading on mucky clay consolidation, we conducted indoor model tests by employing conventional vacuum preloading, ventilated vacuum preloading, and air-injected vacuum preloading, respectively. Analyzing variations in soil settlement, water content, shear strength, soil particle morphology, and micro-pore structure revealed the following findings: in comparison to conventional vacuum preloading, soil settlement increased by approximately 5.6% and 12.3% with ventilated and air-injected vacuum preloading, respectively. Soil microstructure exhibited increased uniformity and density, transitioning from point contact to surface contact between particles. Additionally, both the diameter and quantity of soil pores evidently reduced. Ventilated and air-injected vacuum preloading significantly augmented the shear strength of deep soil, resulting in a more uniform soil matrix. Notably, air-injected vacuum preloading consistently demonstrated superior consolidation performance among the three methods, elevating deep soil shear strength by 11.2 kPa.

Key words: ventilated vacuum preloading, air-injected vacuum preloading, mucky clay, shear strength, soil particle morphology, micro-pore structure