soilStrength: Estimation of precompression stress by Severiano et al....

In soilphysics: Soil Physical Analysis

Estimation of precompression stress by Severiano et al. (2013)

Description

It calculates the precompression stress using the pedo-transfer function from Severiano et al. (2013)

Usage

soilStrength(clay.content, matric.suction = NULL, water.content = NULL)

Arguments

clay.content	a numeric vector containing the values of clay for each soil layer, %. Note that it can also be a unique value.
matric.suction	a numeric vector containing the values of matric suction for each clay content, kPa.
water.content	a numeric vector containing the values of water content for each clay content, m^3 m^{-3}. Note that water.content must be passed if matric.suction is not. See details.

Details

Intervals of soil water content/matric suction to be used as input for estimating soil strength according to Severiano et al. (2013).

Value

A two-columns data frame:

Pc	the precompression stress (Severiano et al. 2013)
LL.Pc	the lower limit of precompression stress in acoording to the Terranimo model criteria (see Stettler et al. 2014). Note: LL.Pc = Pc*0.5
UL.Pc	the upper limit of precompression stress in acoording to the Terranimo model criteria (see Stettler et al. 2014). Note: UL.Pc = Pc*1.1

Author(s)

Renato Paiva de Lima <[e-mail]>

Anderson Rodrigo da Silva <[e-mail]>

Alvaro Pires da Silva <[e-mail]>

References

Severiano, E.C; Oliveira, G.C.; Dias Junior, M.S.; Curi, N.C.; Costa, K. A.P.; Carducci, C.E. 2013. Preconsolidation pressure, soil water retention characteristics, and texture of Latosols in the Brazilian Cerrado. Soil Research, 51:193-202.

Stettler, M., Keller, T., Weisskopf, P., Lamande, M., Lassen, P., Schjonning, P., 2014. Terranimo - a web-based tool for evaluating soil compaction. Landtechnik, 69:132-137.

See Also

stressTraffic

Examples

# EXEMPLE 1 (using water content)
soilStrength(clay.content=c(25,28,30,30,30),
             water.content = c(0.26,0.27,0.29,0.32,0.32))


# EXEMPLE 2 (using matric suction)
soilStrength(clay.content=c(25,28,30,30,30),
             matric.suction = c(100,330,1000,3000,5000))


# EXAMPLE 3 (combining it with soil stress)
stress <- stressTraffic(inflation.pressure=200,
	        recommended.pressure=200,
	        tyre.diameter=1.8,
	        tyre.width=0.4,
	        wheel.load=4000,
	        conc.factor=c(4,5,5,5,5,5),
                layers=c(0.05,0.1,0.3,0.5,0.7,1),
	        plot.contact.area = FALSE)

strength <- soilStrength(clay.content=c(25,28,30,30,30,30),
              matric.suction = c(30,100,100,100,200,200))


# Graph
plot(x = 1, y = 1,
     xlim=c(0,300),ylim=c(1,0),xaxt = "n",
     ylab = "Soil Depth",xlab ="", type="l", main="")
axis(3)
mtext("Vertical Stress",side=3,line=2.5)

stressz <- stress$Stress$sigma_vertical
layers <- stress$Stress$Layers
points(x=stressz, y=layers, type="l")

# Green zone
x0 <- strength$LL.Pc
x1 <- rep(0,length(layers))
y0 <- layers
y1 <- rev(layers)
polygon(x=c(x0,x1), y = c(y0,y1),density = NA,
       col=rgb(red=0, green=1, blue=0, alpha=0.3))

# Yellow zone
x0 <- strength$UL.Pc
x1 <- rev(strength$LL.Pc)
y0 <- layers
y1 <- rev(layers)
polygon(x=c(x0,x1), y = c(y0,y1),density = NA,
       col=rgb(red=1, green=1, blue=0, alpha=0.3))

# Red zone
x0 <- rep(300,length(layers))
x1 <- rev(strength$UL.Pc)
y0 <- layers
y1 <- rev(layers)
polygon(x=c(x0,x1), y = c(y0,y1),density = NA,
       col=rgb(red=1, green=0, blue=0, alpha=0.3))

# End (not run)

soilphysics documentation built on June 7, 2022, 5:06 p.m.