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Publication Number: FHWA-HRT-04-097
Date: August 2007
Measured Variability Of Southern Yellow Pine - Manual for LS-DYNA Wood Material Model 143
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1.9 MODEL INPUT
The previous eight subsections reviewed the behavior and properties of wood and the theory of the model. Here, we examine the effects of moisture content, temperature, and grade on model input parameters. Two methods are available for wood model input. One method is to provide the following input parameters:
These 29 parameters are listed in table 13 and were discussed in detail throughout this section (“Theoretical Manual”). Any consistent system of units may be used.
A second method is to request default material properties. Default material property requests are listed in table 14. This method is convenient because it allows the user to bypass the manual input of the material parameters.
Default material properties are provided for southern yellow pine and Douglas fir as a function of moisture content, temperature, grade, and units. A discussion of the effects of moisture, temperature, and grade is given in the following three subsections. Four consistent sets of units are available. Most of the default material properties are obtained from clear wood samples tested by FPL.(14)
In addition to the choice between user-supplied and default input parameters, the user may also specify control parameters. Control parameters include material identification, density, options to plot damage, increasing the maximum number of iterations performed by the plasticity algorithm, turning on/off the rate effects, overriding perfect plasticity, and controlling perpendicular erosion.