Classify a soil using the Unified Soil Classification System (USCS)

Determines the USCS group symbol and descriptive name (ASTM D2487) for a soil sample. Inputs can be provided as percent components and gradation coefficients, or derived automatically from a grain-size distribution and Atterberg limits.

Usage

USCS(
  pg = NA,
  ps = NA,
  pf = NA,
  Cc = NA,
  Cu = NA,
  LL = NA,
  PL = NA,
  PI = NA,
  sieve = NA,
  size = NA,
  percent = NA,
  metric = T,
  spanish = F
)

Arguments

pg

Numeric. Percent gravel. Default NA.

ps

Numeric. Percent sand. Default NA.

pf

Numeric. Percent fines. Default NA.

Cc

Numeric. Curvature coefficient. Default NA.

Cu

Numeric. Uniformity coefficient. Default NA.

LL

Numeric. Liquid limit (percent). Default NA.

PL

Numeric. Plastic limit (percent). Default NA.

PI

Numeric. Plasticity index (percent). Default NA; computed from LL and PL when missing.

sieve

Numeric vector of ASTM sieve numbers. Used to derive size when size is NA. Default NA.

size

Numeric vector of particle sizes. Default NA.

percent

Numeric vector of percent passing values (0–100). Default NA.

metric

Logical. If TRUE (default) size is in millimetres.

spanish

Logical. If TRUE the group name is returned in Spanish; default FALSE (English).

Value

A named list with:

symbol

USCS group symbol (character).

name

Descriptive group name (character).

pg

Percent gravel.

ps

Percent sand.

pf

Percent fines.

Cu

Uniformity coefficient (only for coarse soils with \(pf \le 12\)).

Cc

Curvature coefficient (only for coarse soils with \(pf \le 12\)).

Details

This function is taken from the "geotech" package from James Kaklamanos

See also

Other soil mechanics, classification: Dsize(), USCS.coarse.symbol(), USCS.fine.symbol(), grainSize.coefs(), percentComponents(), size.from.sieve()

Examples

USCS(pg = 15, ps = 34, pf = 51, Cc = 1, Cu = 4, LL = 40, PL = 10)
#> $symbol
#> [1] "CL"
#> 
#> $name
#> [1] "Sandy lean clay with gravel"
#> 
#> $pg
#> [1] 15
#> 
#> $ps
#> [1] 34
#> 
#> $pf
#> [1] 51
#>