Nonlinear Consolidation Analysis of Soft Soils with Vertical Drains Considering Variable Well Resistance with Time and Depth under Multistage Loading

Acknowledgments

Notation

a

depth-dependent parameter of discharge capacity;

b

reduction rate of discharge capacity with time;

C_h1

k_h1/m_v1γ_w;

c_c

compressibility index;

c_k

permeability index;

d_e

diameter of the influence zone;

e

void ratio of soils;

e₀

initial void ratio of soils;

e₁

reference void ratio of soils corresponding to ${\overline{\sigma }}_1^{\mathrm{\prime }}$;

F_s

parameter concerned with smear effects;

k_h

horizontal permeability coefficient of soils;

k_h1

reference permeability coefficient of soils corresponding to e₁;

k_s

permeability coefficient of soils at r = r_w;

k_w

permeability coefficient of vertical drains;

k_w0

initial permeability coefficient of vertical drains;

l

thickness of the soil layer;

m_v

coefficient of volume compressibility of soils;

n

r_e/r_w;

q(t)

multistage loading;

q_k

stable value of the kth-stage loading;

q_u

final value of multistage loading;

r

radial coordinate;

r_e

radius of the influenced zone;

r_s

radius of the smear zone;

r_w

radius of the vertical drain;

S_t

settlement of the soil layer at the time t;

T_h

$C_{h1}t/d_e^2$;

t

time;

t_2k−2, t_2k

initial and final times of the kth-stage loading;

${\overline{U}}_{pt}$

average degree of consolidation in terms of excess pore-water pressure;

${\overline{U}}_{st}$

average degree of consolidation in terms of settlement;

u_r

excess pore-water pressure at any point in soil;

${\overline{u}}_r$

average excess pore pressure in u_r;

u_w

excess pore-water pressure in the vertical drain;

z

vertical coordinate;

ɛ_v

volumetric strain of soils;

γ_w

specific gravity of water;

γ′

effective gravity of soils;

${\overline{\sigma }}^{\mathrm{\prime }}$

average effective stress of soils;

${\overline{\sigma }}_0^{\mathrm{\prime }}$

initial average effective stress of soil;

${\overline{\sigma }}_1^{\mathrm{\prime }}$

reference average effective stress of soil; and

${\overline{\sigma }}_z^{\mathrm{\prime }}$

average effective stress along depth z.

References