geotech (version 1.0)

lateralEarthPressures: Lateral Earth Pressures

Description

These functions are used to calculate lateral earth pressure coefficients using different methods.

Usage

K(sigmax, sigmaz)
Ko(phi, OCR = 1)
Ka(phi, beta = 0)
Kp(phi, beta = 0)

Arguments

sigmax

horizontal effective stress

sigmaz

vertical effective stress

phi

effective friction angle (deg)

OCR

overconsolidation ratio; default = 1

beta

angle of backfill (deg); default = 0

Value

• K = Coefficient of lateral earth pressure (directly from provided stresses)
• Ko = Coefficient of lateral earth pressure at rest
• Ka = Coefficient of lateral earth pressure (active)
• Kp = Coefficient of lateral earth pressure (passive)

Details

These functions either compute the lateral earth pressure coefficient from provided stresses (K), common empirical correlations (Ka), or basic lateral earth pressure theories (Kp).

• For Ko, the Jaky (1944) equation is used for normally consolidated soil, and the Mayne and Kulhawy (1982) equation is used for overconsolidated soil.
• For Ka and Kp, the basic Rankine (1857) theory is used. Note that this theory requires beta <= phi.="" <="" li="">

References

Jaky, J. (1944). "The Coefficient of Earth Pressure at Rest", Journal for the Society of Hungarian Architects and Engineers, October, pp. 355-358.

Mayne, P.W., and Kulhawy, F.H. (1982). "Ko-OCR Relationships in Soil", Journal of the Geotechnical Engineering Division, ASCE, Vol. 108, No. GT6, pp. 851-872. Rankine, W.J.M. (1857). "On the Stability of Loose Earth", Philosophical Transactions of the Royal Society, Vol. 147, London.

See Also

stressHorizontal

Examples

##  Example code for Coefficient of lateral earth pressure
K(sigmax = 50, sigmaz = 90)

##  Example code for Coefficient of lateral earth pressure at rest
Ko(phi = 20, OCR = 1)

##  Example code for Coefficient of lateral earth pressure (active)
Ka(phi = 30, beta = 10)

##  Example code for Coefficient of lateral earth pressure (passive)
Kp(phi = 30, beta = 10)