Abstract:

To investigate the fundamental physical properties of foamed mixture lightweight soil using river sludge (FMLSS), river sludge collected from a river in Suzhou was used as the research material. An optimized orthogonal test was conducted to study the effects of various factors on the density and permeability of FMLSS, and sensitivity analysis was performed using the range analysis method. Results show that: 1) The density of FMLSS decreased significantly with increasing air foam content and water content, but increased significantly with increasing cement content, and changed slightly with increasing curing age. 2) The permeability coefficient of FMLSS increased with rising air foam content, reduced with increasing cement content, nearly multiplied with increasing water content in a linear manner, and plunged with extending curing age before gradually stabilizing. 3)Density was most sensitive to air foam content, followed by water content, cement content, and curing age in a descending order; permeability coefficient was most sensitive to water content, followed by curing age, cement content, and air foam content in a descending order. 4)In engineering applications, air foam content should be the primary control factor for density and lightweight properties of FMLSS, while water content should be the primary control factor for permeability coefficient. The research findings serve as valuable reference for the resource utilization of dredged silt and environmental protection.

Key words: foamed mixture lightweight soil using river sludge, physical properties, density, permeability coefficient, orthogonal test, sensitivity analysis