Abstract:
To further enhance the shear strength characteristics of sandy soils cured by enzyme-induced carbonate precipitation (EICP) technology, and to improve the brittle damage characteristics of the cured sandy soils, the abandoned disposable masks were blended into the sandy soils for improvement. Based on the triaxial compression test, the influence of different contents of the mask on the shear strength of EICP solidified sand was studied. However, the change of the shear strength characteristics of improved sand and the benefit of mask reinforcement were analyzed after changing the EICP drip rounds and the initial relative compactness of sand. The results show that the best content of the mask is 0.2%. At this time, the peak partial stress of improved sandy soil increases by 59.9%-34% under different confining pressures, the cohesive force increases by 188%, and the internal friction angle increases by 14.5%. The post-peak strength loss is effectively reduced and the brittle damage of cured sand is improved. However, increasing the number of drip rounds and relative compactness could increase the peak partial stress, cohesive force and internal friction angle, but the effect of mask reinforcement is slightly weakened. Finally, mask reinforcement can improve the calcium carbonate generation rate, and the calcium carbonate generation rate increases with the increase of drip rounds, but decreases with the increase of relative compactness.