# stressHorizontal: Horizontal Stress Calculations In geotech: Geotechnical Engineering

## Description

These functions calculate horizontal stress at a point (sigmaX) and versus depth (sigmaX.profile)

## Usage

 ```1 2 3 4``` ```sigmaX(gamma, thk = NA, depth = NA, zw, zout, K, gammaW = NA, metric, upper = TRUE) sigmaX.profile(gamma, thk = NA, depth = NA, K, zw, zout = NA, gammaW = NA, metric) ```

## Arguments

 `gamma` vector of unit weights (pcf or kN/m^3) `thk` vector of layer thicknesses (ft or m) `depth` vector of layer bottom depths (ft or m) `zw` depth of groundwater table (ft or m) `zout` desired depth of output (ft or m) `K` vector of lateral earth pressure coefficients `gammaW` unit weight of water (default = 62.4 pcf for English units;9.81 kN/m^3 for metric units) `metric` logical variable: TRUE (for metric units) or FALSE (for English units) `upper` logical variable when using the sigmaX function to specify whether the upper (TRUE) or lower (FALSE) lateral earth pressure coefficient should be used, for the special case that zout corresponds to a layer interface

## Details

• Either layer thicknesses or depths to layer bottoms must be specified.

• The argument zout should be a single value for sigmaX, and a vector of values for sigmaX.profile. For sigmaX.profile, zout defaults to critical locations in the profile (the top and bottom of the profile, layer interfaces, and the groundwater table) [recommended].

## Value

Function sigmaX outputs a three-element list giving the stresses at a specified depth:

• sigmaX.eff = effective horizontal stress

• sigmaX.total = total horizontal stress

• u = pore water pressure

Function sigmaX.profile outputs a four-element list giving the stress variation with depth (four vectors):

• depth = depth

• sigmaX.eff = effective horizontal stress

• sigmaX.total = total horizontal stress

• u = pore water pressure

## Author(s)

James Kaklamanos <[email protected]> and Kyle Elmy <[email protected]>

`lateralEarthPressures`, `stressPlot`, `stressVertical`
 ```1 2 3 4 5 6 7``` ```## Example code for Horizontal Stress at a point sigmaX(gamma = c(108, 116), depth = c(15, 40), zout = 18, K = c(0.34, 0.32), zw = 15, metric = FALSE, upper = TRUE) ## Example code for Horizontal Stress Profile sigmaX.profile(gamma = c(108, 116), depth = c(15, 40), K = c(0.34, 0.32), zw = 15, metric = FALSE) ```