Class Ifc4::IfcConstructionResource

Nested Relationships

This class is a nested type of Struct Ifc4.

Inheritance Relationships

Base Type

Derived Types

Class Documentation

class Ifc4::IfcConstructionResource : public Ifc4::IfcResource

IfcConstructionResource is an abstract generalization of the different resources used in construction projects, mainly labor, material, equipment and product resources, plus subcontracted resources and aggregations such as a crew resource.

A resource represents “use of something” and does not necessarily correspond to a single item such as a person or vehicle, but represents a pool of items having limited availability such as general labor or an equipment fleet. A resource can represent either a generic resource pool (not having any task assignment) or a task-specific resource allocation (having an IfcTask assignment).

HISTORY New entity in IFC2x2.

IFC2x4 CHANGE Modified in to promote ResourceIdentifer and ResourceGroup (renamed to LongDescription) to supertype IfcResource and add attributes as described.

Type use definition IfcConstructionResource defines the occurrence of any construction resource; common information about construction resource types is handled by IfcConstructionResourceType. The IfcConstructionResourceType (if present) may establish the common type name, common properties, common cost rates, and common productivities applied to specific task types. The IfcConstructionResourceType is attached using the IfcRelDefinesByType.RelatingType objectified relationship and is accessible by the inverse IsTypedBy attribute as shown in Figure 186. The resource type may provide shared productivity and cost information, allowing tasks and resources to be selected according to lowest cost and/or shortest duration. Given an IfcProduct of a particular IfcTypeProduct type, an IfcTypeProcess may be selected from those assigned to the product type using IfcRelAssignsToProduct, and an IfcTypeResource may be selected from those assigned to the process type using IfcRelAssignsToProcess. Then IfcTask and IfcConstructionResource occurrences may be instantiated from the type definitions, applying productivitity and rate information to assigned quantities to calculate ResourceTime.ScheduleWork. Task durations can then be calculated by dividing ResourceTime.ScheduleWork by ResourceTime.ScheduleUsage.

Figure 186 — Construction resource type use

Composition use definition Resources may be decomposed into allocation pools using the IfcRelNests relationship as shown in Figure 187. For example, an IfcLaborResource for “Electrician” may be decomposed into three task-specific IfcLaborResource objects: “Electrical Rough-in”, “First Floor Circuits”, and “Second Floor Circuits”. Both relating and related sides may represent the same ResourceTime.ScheduleUsage quantity (for example, 6 workers time-shared), or the related side may break out ResourceTime.ScheduleUsage quantities for reserved use (for example, 4 workers and 2 workers). A common scenario is two nesting levels where the first-level resources have no task assignments; while second-level resources have specific task assignments indicating that the resource is subdivided into allocations for specific tasks. While the model allows unlimited nesting of resources, implementer agreements may restrict to two nesting levels with task assignments specifically at the second level.

Figure 187 — Construction resource composition use

Declaration use definition A root-level resource (specifically IfcCrewResource or IfcSubContractResource) is declared within the project by IfcRelDeclares where RelatingContext refers to the single IfcProject and RelatedObjects refers to one or more IfcConstructionResource, and other root-level objects within the project.

Assignment use definition A resource may be assigned to an actor by IfcRelAssignsToActor where RelatingActor refers to an IfcActor and RelatedObjects refers to one or more IfcConstructionResource or other objects. Such relationship indicates the actor responsible for allocating the resource such as partitioning into task-specific allocations, delegating to other actors, and/or scheduling over time. Note that this assignment does not indicate the person or organization performing the work; that is indicated by IfcRelAssignsToResource. The actor responsible for the resource may or may not be the same as any actor(s) performing work. A resource may be assigned to a control by IfcRelAssignsToControl where RelatingProduct refers to an IfcControl and RelatedObjects refers to one or more IfcConstructionResource or other objects. Most commonly an IfcWorkCalendar is assigned indicating availability of the resource, where such calendar is nested within a base calendar or an IfcWorkPlan which in turn is assigned to the IfcProject. A resource may be assigned to a group by IfcRelAssignsToGroup where RelatingGroup refers to an IfcGroup and RelatedObjects refers to one or more IfcConstructionResource or other objects. Most commonly an IfcAsset is assigned indicating the asset to be tracked, where such asset is nested within an IfcInventory which in turn is assigned to the IfcProject. A resource may be assigned to a product by IfcRelAssignsToProduct where RelatingProduct refers to an IfcProduct and RelatedObjects refers to one or more IfcConstructionResource or other objects. Most commonly an IfcElement subtype is assigned indicating the product to be constructed, where such product is connected to a spatial structure which in turn is aggregated within the IfcProject. A resource may be assigned to a process by IfcRelAssignsToProcess where RelatingProcess refers to an IfcProcess and RelatedObjects refers to one or more IfcConstructionResource or other objects. Most commonly an IfcTask is assigned indicating the task to be performed by the resource, where such task is nested within a summary task which in turn is assigned to the IfcProject. A resource may have assignments of other objects using IfcRelAssignsToResource where RelatingResource refers to the IfcConstructionResource and RelatedObjects refers to one or more objects such as IfcActor or IfcProduct subtypes. This relationship indicates specific objects assigned to fulfill resource usage. Figure 188 illustrates resource assignment.

Figure 188 — Construction resource assignment use

Constraint use definition Constraints may be applied to a resource to indicate fixed work (such as total person-hours) or fixed usage (such as simultaneous workers). The relationship IfcRelAssociatesConstraint is used where RelatingConstraint points to an IfcMetric and RelatedObjects includes the IfcConstructionResource as shown in Figure 189. IfcRelAssociatesConstraint.Name identifies the attribute to be constrained using a period (“.”) to dereference; for example, “ResourceTime.ScheduleWork” refers to the ScheduleWork attribute on the IfcResourceTime entity referenced on the ResourceTime attribute. The following attributes may be constrained:

‘ResourceTime.ScheduleUsage’: Indicate fixed usage (e.g. simultaneous workers) with ConstraintGrade=HARD and Benchmark=EQUALTO such that changes to ResourceTime.ScheduleWork should impact the assigned IfcTask.TaskTime.ScheduleDuration and vice-versa ‘ResourceTime.ScheduleWork’: Indicate fixed work (e.g. total person-hours) with ConstraintGrade=HARD and Benchmark=EQUALTO such that changes to ResourceTime.ScheduleUsage should impact the assigned IfcTask.TaskTime.ScheduleDuration and vice-versa.

Figure 189 — Construction resource constraint use

Time series use definition Time series may be applied to a resource to indicate the break-out of attribute values over time. The relationship IfcRelAssociatesTimeSeries is used where RelatingTimeSeries points to an IfcTimeSeries (either IfcRegularTimeSeries or IfcIrregularTimeSeries) and RelatedObjects includes the IfcConstructionResource as shown in Figure 190. IfcRelAssociatesTimeSeries.Name identifies the attribute to be constrained using a period (“.”) to dereference; for example, “ResourceTime.ScheduleWork” refers to the ScheduleWork attribute on the IfcResourceTime entity referenced on the ResourceTime attribute. Refer to attribute descriptions on IfcResourceTime for attribute-specific usage. Each IfcTimeSeriesValue indicates a LIST of values, where the sequence of the value corresponds to the IfcCostValue at IfcConstructionResource.CostRatesConsumed. For example, if CostRatesConsumed has two IfcCostValue items in the LIST, “Standard” and “Overtime”, then IfcTimeSeriesValue(IfcDuration(‘T8H0M0S’),IfcDuration(‘T2H0M0S’)) would indicate 8 hours at Standard rate and 2 hours at Overtime rate. If the list of values at IfcTimeSeriesValue.ListValues is less than the size of CostRatesConsumed, then subsequent values are considered to be zero.

Figure 190 — Construction resource time series use

Document use definition Documents may be published for work plans consisting of schedules, calendars, tasks, and resources. The relationship IfcRelAssociatesDocument may be used to preserve mappings to such document where RelatingDocument points to an IfcDocumentReference and RelatedObjects includes the IfcConstructionResource as shown in Figure 191. IfcDocumentReference.ItemReference identifies the resource within the scope of the document, such as an integer or guid. The IfcDocumentReference.ReferencedDocument corresponds to the document which is uniquely identified by IfcDocumentInformation.DocumentId and/or IfcDocumentInformation.PublicationLocation. Such document mapping allows items in the document to be updated from the building information model and vice-versa.

Figure 191 — Construction resource document use

Baseline use definition A resource may have any number of baselines defined using the relationship IfcRelDefinesByObject where RelatingObject is the “current” resource and RelatedObjects consists of multiple “baseline” resources, each representing a copy of the resource as it existed at an earlier point in time as shown in Figure 192. Each baseline IfcConstructionResource is identified by its nested IfcRelAssignsToControl relationship to an IfcWorkSchedule having PredefinedType=BASELINE, IfcWorkSchedule.CreationDate indicating the date of the baseline, and IfcWorkSchedule.Name indicating the name of the baseline.

Figure 192 — Construction resource baseline use

Subclassed by Ifc4::IfcConstructionEquipmentResource, Ifc4::IfcConstructionMaterialResource, Ifc4::IfcConstructionProductResource, Ifc4::IfcCrewResource, Ifc4::IfcLaborResource, Ifc4::IfcSubContractResource

Public Types

typedef IfcTemplatedEntityList<IfcConstructionResource> list

Public Functions

bool hasUsage() const

Whether the optional attribute Usage is defined for this IfcConstructionResource.

::Ifc4::IfcResourceTime *Usage() const
void setUsage(::Ifc4::IfcResourceTime *v)
bool hasBaseCosts() const

Whether the optional attribute BaseCosts is defined for this IfcConstructionResource.

IfcTemplatedEntityList<::Ifc4::IfcAppliedValue>::ptr BaseCosts() const
void setBaseCosts(IfcTemplatedEntityList<::Ifc4::IfcAppliedValue>::ptr v)
bool hasBaseQuantity() const

Whether the optional attribute BaseQuantity is defined for this IfcConstructionResource.

::Ifc4::IfcPhysicalQuantity *BaseQuantity() const
void setBaseQuantity(::Ifc4::IfcPhysicalQuantity *v)
const IfcParse::entity &declaration() const
IfcConstructionResource(IfcEntityInstanceData *e)
IfcConstructionResource(std::string v1_GlobalId, ::Ifc4::IfcOwnerHistory *v2_OwnerHistory, boost::optional<std::string> v3_Name, boost::optional<std::string> v4_Description, boost::optional<std::string> v5_ObjectType, boost::optional<std::string> v6_Identification, boost::optional<std::string> v7_LongDescription, ::Ifc4::IfcResourceTime *v8_Usage, boost::optional<IfcTemplatedEntityList<::Ifc4::IfcAppliedValue>::ptr> v9_BaseCosts, ::Ifc4::IfcPhysicalQuantity *v10_BaseQuantity)

Public Static Functions

const IfcParse::entity &Class()