IFC 4.3.1.0 (IFC4X3_ADD1)

# 7.3.3.4 IfcConstructionMaterialResourceType

## 7.3.3.4.1 Semantic definition

The resource type IfcConstructionMaterialType defines commonly shared information for occurrences of construction material resources. The set of shared information may include:

• common productivities
• common cost rates
• common properties within shared property sets

It is used to define a construction material resource specification (the specific resource information that is common to all occurrences of that resource). Resource types may be exchanged without being already assigned to occurrences.

Occurrences of the IfcConstructionMaterialResourceType are represented by instances of IfcConstructionMaterialResource.

Assignment Use Definition

In addition to assignments specified at the base class IfcConstructionResourceType, a construction material resource type may have assignments of its own using IfcRelAssignsToResource where RelatingResource refers to the IfcConstructionMaterialResourceType and RelatedObjects contains one or more IfcTypeProduct subtypes. Such relationship indicates material specifications to be used as input, which is instantiated as an occurrence assigned for each resource occurrence. The IfcGeographicElementType product type may be used to hold the material representation (via IfcRelAssociatesMaterial. There may be multiple chains of production where such product type may have its own task and resource types assigned indicating how to transport or extract such material.

## 7.3.3.4.7 Formal representation

ENTITY IfcConstructionMaterialResourceType
SUBTYPE OF (IfcConstructionResourceType);
PredefinedType : IfcConstructionMaterialResourceTypeEnum;
WHERE
CorrectPredefinedType : (PredefinedType <> IfcConstructionMaterialResourceTypeEnum.USERDEFINED) OR
((PredefinedType = IfcConstructionMaterialResourceTypeEnum.USERDEFINED) AND EXISTS(SELF\IfcTypeResource.ResourceType));
END_ENTITY;

• New resource