Use this option to define the fire resistance parameters for steel member verification with the Eurocode 3 code.
Access
- Select Fire analysis parameters in the Member Definition - Parameters dialog, and then click Fire.
Basic parameters
- Time resistance
- Specifies the required time of fire resistance in minutes.
- The maximum fire resistance time is 120 min.
- Temperature curve
- Evaluates the temperature of gases resulting from the fire according to the select curve:
- Standard ISO 834
- External fire
- Hydrocarbon fire
- Smoldering fire
- Steel member protection
- Select if the member is Protected or Unprotected. Note: The diagram showing the temperature variability curve varies depending on whether the selected steel member is protected or not.
- Section exposition
- Specify how the section is exposed:
- On all sides
- On three sides
- Only the lower flange is exposed.
Properties of fire protection material (Protected element)
- Encasement type
- Select a type of encasement: Hollow or Contour.
- Group of materials
- Select the group of base materials to which the protection material belongs.
- Name of material
- Contains the list of materials available for the selected group.
- Protection thickness
- Specifies the thickness of the insulating layer protecting a column.
- The default protection thickness depends on the selected type of material.
- Unit mass / Specific heat / Thermal conductivity
- These parameters give additional information on the selected material.
- New material
- Opens the New insulating materials dialog which allows you to create, edit, or delete fire protection materials.
Thermal properties (Unprotected element)
Unprotected element
- The Thermal properties of steel field is used to determine:
Unit mass - a default value roa = 7850 kg/m3
Coefficient of heat transfer by convection - a coefficient depending on a selected temperature curve
Configuration factor - a factor which allows accounting for an element shape and position in a structure (more about definition of this factor can be found in recommendations of the ECCS Technical Committee, point III.3); the interval of the parameter variability: <0.01,1>
Member surface emissivity - the interval of the parameter variability: <0.01,1>
Fire emissivity - the interval of the parameter variability: <0.01,1>
Ignore the 'shadow' effect - if this option is selected, then calculations of the ksh factor, used for evaluating the critical temperature of steel, are not performed - in such a situation, the factor will equal 1.0 (it refers only to calculations according to the EN 1993-1-2 code)
- The Additional parameters field is used to determine:
Safety factor for radiation - a default value = 1.0
Safety factor for convection - a default value = 1.0
Safety factor for fire situation - a default value = 1.0
Adaptation factor - a value that accounts for non-uniform heat flow through the section of a beam in bending in fire conditions; a default value = 0.7
- The Member maximal temperature test field evaluates through testing the maximal temperature on the surface of a selected structure member; using sectional parameters of a member and values defined in the above dialog, the maximal temperature that an element will reach after a determined time resistance is calculated; selecting the Member temperature - user-defined option allows the user to omit the automatic evaluation of the element temperature and to define user's own temperature
- The Temperature Variability Curve diagram presents the way the maximal temperature on the member surface changes in time (the red curve); the blue curve illustrates variability of the temperature of gases resulting from fire in time.