gdp_data {WoodSimulatR}

Means and standard deviations of grade determining properties (GDPs) from literature

Description

Means and standard deviations of grade determining properties (GDPs) from literature

Usage

gdp_data

Format

species

Wood species as a four letter code according to EN 13556. Currently, this is always "PCAB" for Norway spruce (Picea abies).

loadtype

Kind of destructive testing applied to the material – "t" for material tested in tension, "be" for material tested in bending.

project

Research project from which the data originated; "null" if unknown or not applicable.

country

Country from which the material originated, as a two letter country code.

share

Number of pieces on which the values are based.

f_mean, f_sd

Mean and standard deviation of strength, in N/mm².

E_mean, E_sd

Mean and standard deviation of the static modulus of elasticity, in N/mm².

rho_mean, rho_sd

Mean and standard deviation of density, in kg/m³.

literature

Reference to the literature source; "null" if not published yet.

subsample

For distinguishing multiple rows with the same species, loadtype and country – if there are no duplicates, it is the same as country; if there are duplicates, it is country plus a suffixed number separated by "_".

Details

For simulation of an entire dataset with different subsamples with different characteristics (see simulate_dataset), it may be useful to be able to refer to existing results from literature as a basis.

In the dataset gdp_data, means and standard deviations for a number of such subsamples have been collected.

The GDP values collected in gdp_data were selected from publications which aimed at representative sampling within the respective countries. All the same, care must be taken when using these values, due to the natural high variability of timber properties.

Source

The values have been extracted from the following publications:

Ranta-Maunus, Alpo, Julia K. Denzler, and Peter Stapel. 2011. Strength of European Timber. Part 2. Properties of Spruce and Pine Tested in Gradewood Project. VTT.

Rohanová, Alena, and Erika Nunez. 2014. "Prediction Models of Slovakian Structural Timber." Wood Research 59 (5): 757–69.

Stapel, Peter, and Jan-Willem G. van de Kuilen. 2014. “Efficiency of Visual Strength Grading of Timber with Respect to Origin, Species, Cross Section, and Grading Rules: A Critical Evaluation of the Common Standards.” Holzforschung 68 (2): 203–16.