Structural Steel Properties
Description
Definition of the material properties for a section or beam is a three step process:
- Add the material type (concrete / reinforcing steel / etc.)
- Define a set of properties for that material type ((yield strength etc.)
- Allocate the material properties defined in 1 & 2 to the relevant parts of the section or beam section component.
This form performs the second of these 3 stages for structural steel.
As data is entered the program checks that values are within the expected range for steel. This check will highlight any values in error by a factor of 10 more.
Relevant nationally determined parameters are displayed in this form, but these may only be edited in the Nationally Determined Parameters Form accessible through the NDP Values button.
Form Graphic
Field Help
Steel Grade
The CEN primary designation for steel grades is S followed by a 3 digit number which is the yield strength for material up to 16mm thick. EN 10025 is the product standard for plates and open sections, and the common steel grades are listed in this field. Select the required grade, then specify the yield strength according to the plate thickness. (Separate material property sets must be defined for different steel thicknesses).
The yield strengths according to EN 10025 are as follows:
| t<=16 | 16<t<=40 | 40<t<=63 | 63<t<=80 | 80<t<=100 | 100<t<=150 | |
|---|---|---|---|---|---|---|
| S275 | 275 | 265 | 255 | 245 | 235 | 225 |
| S355 | 355 | 345 | 335 | 325 | 315 | 295 |
| S420 | 420 | 400 | 390 | 370 | 360 | 340 |
| S460 | 460 | 440 | 430 | 410 | 400 | 380 |
Yield Strength fy
Enter the yield strength of the structural steel allowing for the plate size according to the table above from EN 10025. A warning will be issued if the value entered is unrealistic, but the value will not be rejected.
Modulus of elasticity
Enter the modulus of elasticity of the steel. The default value of 210,000MPa is obtained from EN 1993-1-1: Clause 3.2.6.
As elastic modulus, shear modulus and the Poisson's ratio are related, a change of this value will affect one of the three elasticity parameters, in this case the shear modulus.
Poisson's Ratio, ν
Enter the value for Poisson's ratio. The default value is typical for this type of material. As elastic modulus, shear modulus and the Poisson's ratio are related, a change of this value will affect one of the three elasticity parameters, in this case the shear modulus.
Shear Modulus, G
Enter the shear modulus value. As elastic modulus, shear modulus and the Poisson's ratio are related, a change of this value will affect one of the three elasticity parameters, in this case the Poisson's ratio.
Coefficient of thermal expansion
Enter the coefficient of thermal expansion for use in temperature calculations.
The default value is 0.000012 /°C as defined by EN 1991-1-5: Table C.1, or 0.00001 /°C when the steel is being defined for the steel composite design beam (see Note 6 of Table C.1).
Density
Enter the density of the structural steel.
The default value is 77.0 kN/m3. From EN 1991-1-1 Table A.4, the density for steel should be in the range 77.0 to 78.5 kN/m3.
Property name
The program will supply a reference name which provides an identifier to the material property set which is usually unique. This value may be edited to give a more readily recognisable name if required.