Finite Element Analysis of Vertical and Horizontal Drainage Structures under Vacuum Combined Surcharge Preloading

Table 1

Basic physical parameters of the soil layer.

Parameter	Sand cushion	Plain fill	Silt	Mucky soil	Silty clay
Depth (m)	1.0	1.0	8.0	4.0	6.0
Γ (kN/m^3)	18.7	17.0	16.6	18.4	20
υ	0.25	0.35	0.38	0.37	0.37
e0	0.6	0.65	1.6	1.2	0.7
E (kPa)	12,000	3,590	2,380	2,650	4,270
C (kPa)	1	12	8	10	15
Φ (°)	20	15	4	12	17
K (m/s)	1.35 × 10^−3	3.75 × 10^−5	1.55 × 10^−9	6.26 × 10^−8	1.55 × 10^−6

Note: γ is the weight of the soil; υ is Poisson ratio; e₀ and E are initial void ratio and elastic modulus, respectively; C and Φ are the cohesion and internal friction angle of soil, respectively; and k denotes the permeability coefficient.