Experimental Study of the Influence of Excavation Surface Stability and Sand Flowability Caused by Dense Slurry–Earth Pressure Balance Shield Tunneling in Silty Sand Stratum

Table 1

Proportions and physical parameters of the testing slurry.

Name	Bentonite (%)	Clay (%)	Density (g/cm^3)	Funnel viscosity (s)	24 h bleeding rate (%)
BC1	15.38	7.69	1.16	38	0
BC2	14.18	14.89	1.20	45	0
BC3	12.82	23.08	1.25	53	0