This page was saved using WebZIP 6.0.8.918 on 10/09/06 15:41:57.
Address: http://www.iai-international.org/Model/documentation/R20/Online_Documents/Documents/IfcMaterialResource.htm
Title: IFC R2.0 Final  •  Size: 28725  •  Last Modified: Wed, 01 Aug 2001 07:13:14 GMT

Specification for IfcMaterialResource

Link to EXPRESS Definition

EXPRESS Definition

Link to EXPRESS-G Diagram

EXPRESS-G Diagram


Table of contents


Simple Types

  • No Simple Types defined in this Schema
  • Select Types

    A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

    M IfcMaterialPropertySelect
    IfcMaterialSelect

    Enumerations

  • No Enumerations defined in this Schema
  • Class Definitions

    A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

    M IfcMaterial
    IfcMaterialFinish
    IfcMaterialLayer
    IfcMaterialLayerSet
    IfcMaterialLayerSetUsage
    IfcMaterialList

    Functions

    A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

    M IfcMlsTotalThickness


    Schema Semantic Definition

    This schema contains the types and classes which are used to define and manipulate materials and their properties. Materials are defined generically, with references to the usage of materials being made from the relevant classes.

    NOTE:
    The definitions in this schema were included in the IfcPropertyResource schema in Release 1.5.1.


    Select IfcMaterialPropertySelect

    Link to EXPRESS Definition

    EXPRESS Definition

    Select Semantic Definition

    Definition from IAI: Allows the selection of the various types of material property representations. IfcSimpleProperty and IfcSimplePropertyWithUnit were provided in previous versions. In Release 2.0 IfcTable was added to this schema to allow the storage of information where there are multiple values that need to be stored against a single attribute. For example, the acoustic absorption coefficients for materials have multiple values depending on the frequency of the incident sound waves. The absorption coefficients for brick could be represented as follows:

    Frequency (Hz)

    Coefficient

    125

    0.05

    500

    0.02

    2000

    0.05

    History

    New Select Type in IFC Release 2.0

    Select

    IfcSimpleProperty

    IfcSimplePropertyWithUnit

    IfcTable


    Select IfcMaterialSelect

    Link to EXPRESS Definition

    EXPRESS Definition

    Select Semantic Definition

    Definition from IAI: Selection of whether a material, a material layer, a material layer set or a material list is used.

    History

    This Select Type has changed after IFC Release 1.5.1, please see the Migration Guide for details

    Select

    IfcMaterial

    IfcMaterialList

    IfcMaterialLayerSet


    Class IfcMaterial

    Link to EXPRESS Definition

    EXPRESS Definition

    Class Semantic Definition

    Definition from IAI: A homogenous substance that can be used to form elements.

    History

    This Class has changed after IFC Release 1.5.1, please see the Migration Guide for details
    ISSUE: See Issue I342 for IFC Release 1.5.1

    Attribute and Relationship Definitions

    Superclasses and Subclasses

    This Class does not have any Superclasses or Subclasses

    Attributes and Relationships

    Attribute type (OPT, DER, INV)

    Redefinition (SELF)

    Attribute / Relation

    Data or Rel. type

    Definition

     

    MaterialName

     

    STRING

    Name of the material.

    OPT

    MaterialClassification

     

    IfcClassificationList

    The material classifications identifying the type of material.

     

    MaterialFinishes

     

    SET [0:?] OF IfcMaterialFinish

    Finishes that are appropriate for this material. These finishes can be obtained by direct treatment of the surface of the material. This does NOT store information on applied finishes, such as paints, etc

     

    Properties

     

    SET [0:?] OF IfcMaterialPropertySelect

    The list of material properties defined for this material.


    Class IfcMaterialFinish

    Link to EXPRESS Definition

    EXPRESS Definition

    Class Semantic Definition

    Definition from IAI: The properties of a type of finish that can be applied to the material itself (as distinct from an applied finish such as paint).

    NOTE: New in IFC Release 2.0

    History

    New Class in IFC Release 2.0

    Attribute and Relationship Definitions

    Superclasses and Subclasses

    This Class does not have any Superclasses or Subclasses

    Attributes and Relationships

    Attribute type (OPT, DER, INV)

    Redefinition (SELF)

    Attribute / Relation

    Data or Rel. type

    Definition

     

    FinishName

     

    STRING

    Name of the finish treatment

     

    Properties

     

    LIST [0:?] OF IfcMaterialPropertySelect

    List of the surface properties that result from the use of this finish on the material.

    INV

    ForMaterial

     

    IfcMaterial

    Reference to the material to which this finish is applied. Note: each Material/Finish combination will have unique attributes


    Class IfcMaterialLayer

    Link to EXPRESS Definition

    EXPRESS Definition

    Class Semantic Definition

    Definition from IAI: A single and identifiable part constructed from a single material of an element which is constructed from a number of layers. For example, a cavity wall with brick masonry used in each leaf would be modeled using three IfcMaterialLayers.

    History

    This Class has changed after IFC Release 1.5.1, please see the Migration Guide for details
    ISSUE: Issue I327 for IFC Release 1.5.1

    Attribute and Relationship Definitions

    Superclasses and Subclasses

    This Class does not have any Superclasses or Subclasses

    Attributes and Relationships

    Attribute type (OPT, DER, INV)

    Redefinition (SELF)

    Attribute / Relation

    Data or Rel. type

    Definition

     

    Material

     

    IfcMaterial

    Material from which the material layer is constructed.

     

    OffsetFromMLSBase

     

    IfcLengthMeasure

    The dimensional offset from the datum point of the material layer.

     

    LayerThickness

     

    IfcPositiveLengthMeasure

    The thickness of this layer.

    INV

    ToMaterialLayerSet

     

    IfcMaterialLayerSet

    Reference to the material layer set, in which the material layer is included.


    Class IfcMaterialLayerSet

    Link to EXPRESS Definition

    EXPRESS Definition

    Class Semantic Definition

    Definition from IAI: A designation by which an element which is constructed from a number of material layers is known and through which the relative positioning of individual layers can be expressed. An cavity brick wall would be modeled as IfcMaterialLayerSet consisting of three IfcMaterialLayers – brick, air cavity and brick.

    History

    This Class has changed after IFC Release 1.5.1, please see the Migration Guide for details

    Attribute and Relationship Definitions

    Superclasses and Subclasses

    This Class does not have any Superclasses or Subclasses

    Attributes and Relationships

    Attribute type (OPT, DER, INV)

    Redefinition (SELF)

    Attribute / Relation

    Data or Rel. type

    Definition

     

    HasMaterialLayers

     

    LIST [1:?] OF IfcMaterialLayer

    Identification of the layers from which the material layer set is composed.

     

    IsVentilated

     

    BOOLEAN

    Set to TRUE if there is air exchange from the cavity to the outside air.


    Class IfcMaterialLayerSetUsage

    Link to EXPRESS Definition

    EXPRESS Definition

    Class Semantic Definition

    Definition from IAI: Determines the usage of the material layer set in terms of its offset positioning relative to some baseline and the sense in which the material layers are measured. A cavity brick wall defined as an IfcMaterialLayerSet could be offset from a grid line by 100 mm.

    History

    This Class has changed after IFC Release 1.5.1, please see the Migration Guide for details
    ISSUE: See Issue I-327 for IFC Release 1.5.1

    Attribute and Relationship Definitions

    Superclasses and Subclasses

    This Class does not have any Superclasses or Subclasses

    Attributes and Relationships

    Attribute type (OPT, DER, INV)

    Redefinition (SELF)

    Attribute / Relation

    Data or Rel. type

    Definition

     

    ForLayerSet

     

    IfcMaterialLayerSet

    Layer set to which the usage is applied.

     

    MlsOffsetFromBaseline

     

    IfcLengthMeasure

    Offset from some baseline of the layer set. NOTE: By default, the sense of measurement is left to right and this takes the value TRUE.

     

    MlsSenseLtoR

     

    BOOLEAN

    The sense in which the layer set is measured.

    DER

    TotalThickness

     

    IfcLengthMeasure

    Total thickness of the material layer set is derived from the function IfcMlsTotalThickness


    Class IfcMaterialList

    Link to EXPRESS Definition

    EXPRESS Definition

    Class Semantic Definition

    Definition from IAI: A list of materials that are used in a non-homogenous element.
    This will normally be used where an element is described at a more abstract level. For example, for in an architectural specification writer, the only information that may be needed about a concrete column is that it contains concrete, reinforcing steel and mild steel ligatures.

    History

    This Class has changed after IFC Release 1.5.1, please see the Migration Guide for details

    Attribute and Relationship Definitions

    Superclasses and Subclasses

    This Class does not have any Superclasses or Subclasses

    Attributes and Relationships

    Attribute type (OPT, DER, INV)

    Redefinition (SELF)

    Attribute / Relation

    Data or Rel. type

    Definition

     

    Materials

     

    LIST [1:?] OF IfcMaterial

    Materials used in a composition of substances.


    Function IfcMlsTotalThickness

    Link to EXPRESS Definition

    EXPRESS Definition

    Function Semantic Definition

    Definition from IAI: Calculates the total thickness of a material layer set from the thicknesses of the material layers and their offset from the layer set base.

    History

    This Function has changed after IFC Release 1.5.1, please see the Migration Guide for details