zhuandyin2012

Function summary

zhuandyin2012(z, t, alpha, p, q[, drn, …])

Analysis and mathematical solutions for consolidation of a soil layer with depth-dependent parameters under confined compression.

Module listing

Zhu and Yin (2012) “Analysis and mathematical solutions for consolidation of a soil layer with depth-dependent parameters under confined compression”.

geotecha.consolidation.zhuandyin2012.zhuandyin2012(z, t, alpha, p, q, drn=0, tpor=None, H=1, kv0=1, mv0=0.1, gamw=10, ui=1, nterms=20, plot_eigs=False)

Analysis and mathematical solutions for consolidation of a soil layer with depth-dependent parameters under confined compression.

An implementation of Zhu and Yin (2012) [1]_.

Features:

• Single layer.
• Permeability and volume compressibility can vary with depth with a power lay relationship.
• Instant load uniform with depth.
• PTIB ansd PTPB drainage conditions.
• Pore pressure vs depth at variaous times
• Degree of consolidation based on surface settlement vs time.
• Settlement vs time.

Parameters:

z : float or 1d array/list of float

Depth.

t : float or 1d array/list of float

Time for degree of consolidation calcs.

tpor : float or 1d array/list of float

Time for pore pressure vs depth calcs.

alpha, p, q : float

Exponent in depth dependence of permeability and compressibility respectively. e.g. mv = mv0 * (1+alpha*z/H)**q. Note p/q cannot be 2; alpha cannot be zero.

drn : [0,1], optional

Drainage. drn=0 is pervious top pervious bottom. drn=1 is pervious bottom, impervious bottom. default drn=0.

tpor : float or 1d array/list of float, optional

Time values for pore pressure vs depth calcs. Default tpor=None i.e. time values will be taken from t.

H : float, optional

Drainage path length. default H=1.

kv0 : float, optional

Vertical coefficient of permeability. Default kv=1.

mv0 : float, optional

Volume compressibility. Default mv=0.1.

gamw : float, optional

Unit weight of water. Default gamw=10.

ui : float, optional

Initial uniform pore water pressure. Default ui=1.

nterms : int, optional

maximum number of series terms. default nterms=20.

plot_eigs : True/False, optional

If True then a plot of the characteristic curve and associated eigenvalues will be created. Use plt.show after runnning the program to display the curve. Use this to assess if the eigenvalues are correct. Default plot_eigs=False.

Returns:

por : 2d array of float

Pore pressure at depth and time. ppress is an array of size (len(z), len(t)).

doc : 1d array of float

Degree of consolidation based on surface settlement.

settlement : 1d array of float

Surface settlement at time values

Notes

kv = kv0 * (1+alp*z/H)**p mv = mv0 * (1+alp*z/H)**q

References

Code based on theroy in [1]_

..[1] Zhu, G., and J. Yin. 2012. ‘Analysis and Mathematical Solutions

for Consolidation of a Soil Layer with Depth-Dependent Parameters under Confined Compression’. International Journal of Geomechanics 12 (4): 451-61.