TR.26.1 Define Material
This command may be used to specify the material properties by material name. You will then assign the members and elements to this material name in the CONSTANTS command (See
TR.26.2 Specifying Constants for Members and
Elements for details and an example).
General Format
DEFINE MATERIAL
then
ISOTROPIC name
E f1
G f3
POISSON f6
DENSITY f7
ALPHA f8
DAMPING f10
or
2DORTHOTROPIC name
E f1 (f2)
G f3 (f4) (f5)
POISSON f6
DENSITY f7
ALPHA f8 (f9)
DAMPING f10
Repeat ISOTROPIC or 2DORTHOTROPIC name and values for as many materials as desired then:
END MATERIAL (DEFINITION)
Where:
| Parameter | Description |
|---|---|
| name | material name (name of up to 36 characters) |
| f1, f2 | specifies Young's Modulus (E). (f2 in local Y for 2DOthotropic materials) |
| f3, f4, f5 | specifies Shear Modulus (G). For plates, the following are G values in local directions: f3 is the G for in-plane shear; f4 is the G for transverse shear in the local Y-Z direction; f5 is the G for transverse shear in the local Z-X direction. (Enter only for beams when the Poisson ratio is not in the range of 0.01 to 0.499.) |
| f6 | specifies Poisson's Ratio. If G is not entered, then this value is used for calculating the Shear Modulus (G = 0.5xE/(1+POISSON)). This value must be in the range of 0.01 to 0.499. Poisson's ratio must be entered for orthotropic plates or when Poisson cannot be computed from G. |
| f7 | specifies weight density |
| f8, f9 | Coefficient of thermal expansion. (f9 in local Y for 2DOthotropic materials) |
| f10 | the damping ratio to be used in computing the modal damping by the composite damping method in a dynamic analysis when CDAMP has been specified. Damping must be in the range of 0.001 to 0.990. |
Note: Any material property which you do not explicitly specify is assumed to be the default value.
- f1 defaults to 0.0 but a positive value must be entered or an error will ensue
- f2 defaults to f1
- f3 defaults to 0.5xE/(1+POISSON)
- f4 defaults to f3
- f5 defaults to f4.
- f6 defaults to a sliding scale value based on E (that is: 0.30 when E is near that of steel, 0.33 when E is near that of aluminum, 0.17 when E is near that of concrete) .
- f7 defaults to 0.0
- f8 defaults to 0.0
- f9 defaults to f8
- f10 defaults to 0.0