TMC_Overturning_Critical_wind_speed_functions: Critical wind speed for overturning - Single-tree method.

In tom-locatelli/fgr: R Version of the ForestGALES wind risk model

Description

Calculates the critical wind speed for overturning using the TMC method.

Usage

uh_overturning_tmc(
  tree_ht,
  dbh,
  cr_depth,
  cr_width,
  spacing_current,
  spacing_before,
  years_since_thin,
  dist_edge,
  gap_size,
  moe,
  c_reg,
  stem_vol,
  stem_density,
  crown_density,
  snow_depth,
  snow_density,
  ci,
  ci_value,
  n_drag,
  c_drag,
  drag_upper_limit,
  equivalent_mean_ht,
  stand_cr_depth,
  stand_cr_width,
  fgr_constants
)

uh_overturning_tmc_tmr_simple(
  tree_ht,
  dbh,
  cr_depth,
  cr_width,
  spacing_current,
  spacing_before,
  years_since_thin,
  dist_edge,
  gap_size,
  equivalent_mean_ht,
  moe,
  c_reg,
  stem_vol,
  stem_density,
  crown_density,
  snow_depth,
  snow_density,
  ci,
  ci_value,
  fgr_constants
)

Arguments

tree_ht	Individual tee height (m).
dbh	Diameter of the stem at breast height, i.e. 1.3m above the ground (cm).
cr_depth	Length of the tree crown (m).
cr_width	Width of the tree crown (m).
spacing_current	Current mean spacing of trees in the stand (m).
spacing_before	Mean spacing of trees in the stand before any thinning (m).
years_since_thin	Number of years since most recent thinning.
dist_edge	Distance of tree from the upwind edge (m).
gap_size	Length of the upwind gap (m).
moe	Modulus of Elasticity of green wood (MPa).
c_reg	Regression coefficients of uprooting moment against stem weight (N m kg-1).
stem_vol	Individual tree stem volume (m3).
stem_density	Density of green wood of the stem (kg m-3).
crown_density	Density of of the tree crown (kg m-3).
snow_depth	Depth of layer of snow on tree crown (cm).
snow_density	Density of snow (kg m-3).
ci	Competition Index (bal, heg, none) used.
ci_value	Value of ci.
n_drag	N parameter of the drag coefficient formula (dimensionless).
c_drag	C parameter of the drag coefficient formula (dimensionless).
drag_upper_limit	Maximum wind speed used during the experiments from which n_drag and c_drag were derived (m*s-1).
equivalent_mean_ht	Equivalent mean stand height: the level in the stand responsible for most of the momentum absorption (m).
stand_cr_depth	Length of the crown of the "equivalent mean tree" in the stand (m).
stand_cr_width	Width of the crown of the "equivalent mean tree" in the stand (m).
stand_mean_ht	Arithmetic mean height of the trees in the stand (m).

Value

A list including: The critical wind speed (m s-1) for overturning at canopy top height for the single-tree method; The turning moment coefficient; The turning moment ratio; The deflection loading factor; The critical overturning moment; The combined effect of edge and gap on the applied bending moment.

tom-locatelli/fgr documentation built on Oct. 2, 2020, 2:09 a.m.