A Predictive Settlement Modeling Framework Employing Thermal–Hydraulic–Mechanical–Biochemical Processes in Municipal Solid Waste Landfills

Acknowledgments

Notation

b

mechanical creep coefficient;

C

constant number related to the theoretical upper bound limit of decay rate;

C_c

compressibility index;

C_n

normalization constant;

c

rate constant for mechanical creep;

d

layer depth;

$d{\epsilon }_v$

total volumetric strain;

$d{\epsilon }_v^e$

elastic volumetric strain;

$d{\epsilon }_v^p$

plastic volumetric strain;

e

void ratio;

f_w

water content factor;

H

depth of the waste;

$H_{i,j-1}^0$

initial height of lift i and period j−1;

$H_{ij}^0$

initial height of lift i at the beginning of period j;

k

first-order decay coefficient;

k_st

temperature-saturation-dependent decay rate;

M

frictional constant;

m

linear constants based on the lower and upper bound of k;

n

linear constants based on the lower and upper bound of k;

P′

mean effective stress;

$p_0^{\mathrm{\prime }}$

preconsolidation stress;

q

deviatoric stress;

S

saturation;

S_e

effective saturation;

S_i

average saturation of lift i;

S_max

maximum saturation;

S_MSW

field saturation degree;

S_r

residual degree of saturation;

T

temperature (°C);

T_ij

average temperature of lift i, period j;

t′

onset time after the completion of instant settlement;

u_g

pore air pressure;

ΔH_bij

total biodegradation creep settlement of lift i at period j;

ΔH_ij

total calculated settlement of lift i at the end of period i;

$\mathrm{\Delta }{\sigma }_{se}^{\mathrm{\prime }}$

Bishop’s mean effective stress due to waste placement;

${\epsilon }_{dg}$

total possible biostrain;

${\epsilon }_T$

total strain;

${\epsilon }_{dgij}^0$

initial potential strain of layer i, period j;

${\epsilon }_{dgij}^0$

initial biodegradation strain of ith lift at the beginning of period j;

γ

MSW unit weight;

η

ratio of deviatoric stress and mean effective stress;

κ

swelling index;

λ

compressibility index;

σ

total stress;

σ_h

horizontal stress;

σ_i,j

cumulative stress load of lift i up to j;

σ_v

vertical stress;

${\sigma }_{se}^{\mathrm{\prime }}$

Bishop’s effective stress;

ψ

suction pressure;

θ

volumetric moisture content;

θ_s

saturated moisture content;

θ_r

residual moisture content; and

φ′

internal friction angle.

References