ISO/PAS 12006-3:2001

Building construction — Organization of information about construction works — Part 3: Framework for object-oriented information exchange

Construction immobilière — Organisation de l'information des travaux de construction — Partie 3: Schéma pour l'échange d'information basée sur l'objet

General Information

• Status: Withdrawn
• Publication Date: 17-Oct-2001
• Withdrawal Date: 17-Oct-2001
• ICS: 91.010.01 - Construction industry in general
• Technical Committee: ISO/TC 59/SC 13 - Organization and digitization of information about buildings and civil engineering works, including building information modelling (BIM)
• Drafting Committee: ISO/TC 59/SC 13 - Organization and digitization of information about buildings and civil engineering works, including building information modelling (BIM)
• Current Stage: 9599 - Withdrawal of International Standard
• Completion Date: 17-Apr-2007

Relations

• Revised: ISO 12006-3:2007 - Building construction — Organization of information about construction works — Part 3: Framework for object-oriented information
• Effective Date: 15-Apr-2008

Standards Content (Sample)

PUBLICLY ISO/PAS
AVAILABLE 12006-3
SPECIFICATION
First edition
2001-10-15
Building construction — Organization of
information about construction works —
Part 3:
Framework for object-oriented information
exchange
Construction immobilière — Organisation de l'information des travaux de
construction —
Partie 3: Schéma pour l'échange d'information basée sur l'objet
Reference number
ISO/PAS 12006-3:2001(E)
©
ISO 2001

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ISO/PAS 12006-3:2001(E)
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ISO/PAS 12006-3:2001(E)
Contents Page
Foreword.iv
Introduction.v
1 Scope .1
2 Normative reference .1
3 Terms and definitions .1
4 Specification.1
Annex A (informative) Conventions .22
Bibliography.24
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ISO/PAS 12006-3:2001(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO
member bodies). The work of preparing International Standards is normally carried out through ISO technical
committees. Each member body interested in a subject for which a technical committee has been established has
the right to be represented on that committee. International organizations, governmental and non-governmental, in
liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical
Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3.
The main task of technical committees is to prepare International Standards. Draft International Standards adopted
by the technical committees are circulated to the member bodies for voting. Publication as an International
Standard requires approval by at least 75 % of the member bodies casting a vote.
In other circumstances, particularly when there is an urgent market requirement for such documents, a technical
committee may decide to publish other types of normative document:
� an ISO Publicly Available Specification (ISO/PAS) represents an agreement between technical experts in an
ISO working group and is accepted for publication if it is approved by more than 50 % of the members of the
parent committee casting a vote;
� an ISO Technical Specification (ISO/TS) represents an agreement between the members of a technical
committee and is accepted for publication if it is approved by 2/3 of the members of the committee casting a
vote.
An ISO/PAS or ISO/TS is reviewed every three years with a view to deciding whether it can be transformed into an
International Standard.
Attention is drawn to the possibility that some of the elements of this Publicly Available Specification
ISO/PAS 12006-3 may be the subject of patent rights. ISO shall not be held responsible for identifying any or all
such patent rights.
ISO/PAS 12006-3 was prepared by Technical Committee ISO/TC 59, Building construction, Subcommittee SC 13,
Organization of information about construction works.
ISO 12006 consists of the following parts, under the general title Organization of information about construction
works:
� Part 2: Framework for classification of information
� Part 3: Framework for object-oriented information exchange
ISO 12006-2 provides a framework for a classification, rather than the object-oriented approach of this part of
ISO 12006. The two parts should be regarded as complementary rather than contradictory. Each has been
developed and published in the belief that it has an important role to play in the organization of information about
1)
construction works .
While ISO 12006-2 reflects many years of refinement of classification systems, this part of ISO 12006 represents
not so much new thinking, but a new implementation of established information modelling practice using a new ISO
process which aims to bring new work of this kind into use as quickly as possible. Feedback is a vital component of
the development process and will be welcomed, via the secretariat of ISO/TC 59/SC 13.
Annex A of this part of ISO 12006 is for information only.
1) ISO 12006-1 has been cancelled.
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ISO/PAS 12006-3:2001(E)
Introduction
Over the last few years much work has been undertaken in structuring technical information for construction works.
In particular, two approaches have been pursued within ISO: “classification” and “object-orientation.”
The former has seen the development of a new International Standard, ISO 12006-2, which embraces many of the
classification systems which have arisen since the first formal construction classification, SfB, was introduced in
Sweden in 1950. The general approach taken by these is that they organize things by some characteristic or
aspect, which might be described as “views” or “facets”.
The “object-oriented” approach describes the characteristics of things without a grouping preference or an ordering
by specialization. In the object-oriented approach, the object is central, thus acting as a container of characteristics.
Such an approach is exemplified in International Standards such as those in the ISO STEP series (ISO 10303), or
EPISTLE (ISO 15926). It is also known as “product modelling”. An object can be grouped with the help of
classification systems that take one or more characteristics of the object for the grouping.
A number of ISO technical committees (as well as a number of related bodies outside ISO) considered that these
methodologies needed to be reconciled in order to bring together the overlapping interests of users of computer-
aided drafting systems, specifiers and suppliers of reference material, and form a “content bridge” between new
object-oriented software and older legacy systems, in particular databases of construction information.
In addition to these approaches, several new technologies such as XML (eXtensible Mark-up Language), and IFC
(Industry Foundation Classes), which have special importance for exchange of information about construction
works, are currently under active development and implementation.
At a meeting of representatives of ISO technical committees and other bodies with an interest in construction
information content and exchange technology, held in Vancouver in June 1999, it was agreed that
� a common terminology about objects and their attributes would be beneficial for information exchange in the
construction industry, and
� there should be an International Standard which describes a framework for such a terminology in the form of a
formal information model.
ISO/TC 59/SC 13 formed a working group, WG 6, to develop the standard and it determined that the framework
should provide for
� definition of concepts,
� definition of relations between concepts, and
� naming of concepts (with multilingual capacity).
Real-life objects can be grouped in classes, e.g. the four walls of a given room belong to the conceptual class
“wall”. Relations, properties, etc., and groups of classes can be objects as well, e.g. the size of a wall, or the
U-value of a wall. A model is a representation of a part of the real world, e.g. a model predicting the heat flow
through a wall under given conditions. A meta-model is a model of the model, e.g. if grammar defines how a
language should be used, then grammar is a meta-model for languages. A very formal and precisely defined
language for information models is EXPRESS and its graphical representation EXPRESS-G. In this part of
ISO 12006, EXPRESS and EXPRESS-G are used.
The model specified provides the ability to define concepts. Concepts are objects defined by properties. Objects
and properties can have relationships and can be grouped. Objects, grouping and relationships are the basic
entities of the model. The set of properties or groups of properties associated with an object provide the formal
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ISO/PAS 12006-3:2001(E)
definition of the object as well as its typical behaviour. Properties have values, optionally expressed in units. Values
form the semantic content of a concept, thus providing, through several aggregation levels, its ultimate formal
description.
The role that an object is intended to play can be designated through the model and this provides the capability to
define the context within which the object is used. Each object may have multiple names and this allows for its
expression in terms of synonyms or in multiple languages. Each object is always named in English (the default
language) and may also be named in terms of the language of the location in which it is determined or used.
Objects may be related to formal classification systems through the provision of classification references.
The model has one Root class from which the following three classes inherit: Objects, Groups and the
Relationships between them. The Root class provides the ability to assign any set of names, labels and
descriptions, in any language, to its derived types, as well as identifiers and dates.
Objects are divided into Subjects, References, Activities, Units and Properties. Subjects are the things that are
described. References provide the means to associate external documents, such as standards, regulations and
classification systems, to the Objects. The other classes are description classes related to other Objects and
themselves through Relationships.
Relationships provide an association mechanism between Objects. Relationships are divided into Association,
Specialization, Composition, Involvement (acting upon), Property assignment, Grouping and Value assignment.
Groups provide for all kinds of groups of Objects, including nested Groups, by means of the Grouping
Relationships.
Properties are classes for the storage of data. Data are Values with optionally associated Units, and are assigned
to Properties by means of the Value assignment Relationship. This Relationship makes a distinction between
several – enumerated – Value assignment roles, such as Nominal Values, and Upper or Lower boundary Values.
The meta-model described in this part of ISO 12006 can have numerous uses but its principal potential lies with the
development of the precise “sets of words” needed to maximize the efficiency of product models and e-business for
construction works.
A set of words can be called a terminology, a vocabulary or a lexicon and in this context these terms are more or
less interchangeable. Sets of words have long been published as printed dictionaries but it is expected that the sets
of words which this specification represent, will enable the publishing of electronic dictionaries.
Because this specification has a lexical function — it is to do with the words used in communication about buildings
— the prefix “Lex” has been adopted within the model. For sets of words, “vocabulary” has been used rather than
“terminology” as being the most commonly understood term.
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PUBLICLY AVAILABLE SPECIFICATION ISO/PAS 12006-3:2001(E)
Building construction — Organization of information about
construction works —
Part 3:
Framework for object-oriented information exchange
1 Scope
This part of ISO 12006 specifies a language-independent information model which may be used for the
development of vocabularies used in information about construction works.
It enables classification systems, information models, object models and process models to be referenced from
within acommonframework.
2 Normative reference
The following normative document contains provisions which, through reference in this text, constitute provisions of
this part of ISO 12006. For dated references, subsequent amendments to, or revisions of, any of these publications
do not apply. However, parties to agreements based on this part of ISO 12006 are encouraged to investigate the
possibility of applying the most recent edition of the normative document indicated below. For undated references,
the latest edition of the normative document referred to applies. Members of ISO and IEC maintain registers of
currently valid International Standards.
ISO 10303-11:1994, Industrial automation systems and integration — Product data representation and
exchange — Part 11: Description methods: The EXPRESS language reference manual
3 Terms and definitions
For the purposes of this part of ISO 12006, the terms and definitions given in ISO 10303-11 apply.
4 Specification
ISO/PAS 12006-3, version 1, is described in the EXPRESS-G diagrams shown in Figures 1 to 5. Following those,
the formal definition is given in EXPRESS.
The conventions used in the development of this specification are given in annex A. These conventions do not
apply to the population or use of the framework.
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ISO/PAS 12006-3:2001(E)
TOP LEVEL STRUCTURE
From the Root the model is divided into three main concepts: Objects, Collections and the Relationship between them. Names,
descriptions and identifiers are inherited from the abstract Root object.
Figure 1 — EXPRESS-G diagram 1
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ISO/PAS 12006-3:2001(E)
RELATIONSHIPS
The models have both generic and specific relationships. The most generic relationship is LexRelAssociates which can be given
any name and set of roles through the abstract LexRelationship.
Figure 2 — EXPRESS-G diagram 2
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ISO/PAS 12006-3:2001(E)
SIMPLE TYPES
All text and numbers are assigned through the use of Defined types. All values are stored as Strings while the formatting lies in
the definition of the Defined type.
Figure 3 — EXPRESS-G diagram 3
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ISO/PAS 12006-3:2001(E)
VALUE TYPES
The mechanism to create all types of values and tolerances, which can be assigned to properties. LexValue is not a subtype of
LexRoot.
Figure 4 — EXPRESS-G diagram 4
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ISO/PAS 12006-3:2001(E)
DESCRIPTIVE TYPES
Allows you to add any number of names and descriptions to any object. The names will always be of a particular language. The
model also allow you to name roles of Relationships. LexDescriptiveIdentifier is not a subtype of LexRoot.
Figure 5 — EXPRESS-G diagram 5
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ISO/PAS 12006-3:2001(E)
EXPRESS specification:
*)
SCHEMA ISO_PAS_12006_3_VERSION_1;
(*
LexActivity
The LexActivity can represent any activity or process. An activity is something that makes a change to a subject.
The activity is similar to the concept verb in common speech.
EXAMPLE:
"door assembly" is an activity and may be used to describe the assembly of a door set
"bricklaying" is an activity
"cleaning" is an activity
"building" is an activity
"pumping concrete" is an activity
EXPRESS specification:
*)
ENTITY LexActivity
SUBTYPE OF(LexObject);
END_ENTITY;
(*
LexBoundValue
A LexBoundValue is a value that may exist within a range that is bounded by upper and lower limits. At least one of
the upper bound or lower bound must be asserted.
EXAMPLE:
The value range 13 kg to 120 kg is a LexBoundValue.
EXPRESS specification:
*)
ENTITY LexBoundValue
SUBTYPE OF(LexValue);
UpperBound :OPTIONAL LexSingleValue;
LowerBound :OPTIONAL LexSingleValue;
WHERE
WR1 :EXISTS(UpperBound) OR EXISTS(LowerBound) ;
END_ENTITY;
(*
Attribute definitions:
UpperBound: A value being the upper bound of the bounded value
LowerBound: A value being the lower bound of the bounded value
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ISO/PAS 12006-3:2001(E)
LexCollection
The LexCollection is a grouping mechanism allowing collections containing mixtures of any subtype of LexObject.
A LexCollection can be used to group objects for special purposes or professions.
EXAMPLE:
"steel work" is an example of a LexCollection of all objects, properties and units used in connection with steel work
"pumps" is a LexCollection grouping all types of pumps regardless of where they appear in different hierarchies
"ironmongery" is an example of a LexCollection of objects that have no functional relationship
EXPRESS specification:
*)
ENTITY LexCollection
SUBTYPE OF(LexRoot);
END_ENTITY;
(*
LexDate
LexDate is the date of last revision defined on the format YYYY.MM.DD.
EXAMPLE:
The 31st day of May in the year 2000 should be written as 2000.05.31.
NOTE Date may be more precisely defined by use of a more detailed schema such as that found in the date-time schema
of ISO 10303-41.
EXPRESS specification:
*)
TYPE LexDate = STRING;
END_TYPE;
(*
LexDescription
The LexDescription is a language-dependent description of the concept and may act as a textual definition of the
concept.
EXAMPLE:
"A door panel is normally a door leaf that opens to allow people or goods to pass" is the English explanation for the object "Door
panel".
EXPRESS specification:
*)
ENTITY LexDescription
SUBTYPE OF(LexDescriptiveIdentifier);
Description :LexText;
INVERSE
Describes :LexRoot FOR Description;
END_ENTITY;
(*
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ISO/PAS 12006-3:2001(E)
Attribute definitions:
Description: A text being the description of the object
Describes: The object to which the description applies
LexDescriptiveIdentifier
A LexDescriptiveIdentifier may be a name, a description or a role name. It is language dependent.
EXPRESS specification:
*)
ENTITY LexDescriptiveIdentifier
ABSTRACT SUPERTYPE OF (ONEOF(LexName, LexDescription, LexRoleName));
LanguageName :LexLanguage;
END_ENTITY;
(*
Attribute definitions:
LanguageName: The name of the language used for the LexDescriptiveIdentifier
LexEnumeratedValue
LexEnumeratedValue is a reference to a value selected from a defined list of options that are stored in an
enumerated list of LexSingleValues.
NOTE See LexEnumeration for the collection containing the enumerated values.
EXPRESS specification:
*)
ENTITY LexEnumeratedValue
SUBTYPE OF(LexValue);
EnumerationReference :LexEnumeration;
EnumerationValue :LexSingleValue;
END_ENTITY;
(*
Attribute definitions:
EnumerationReference: Enumeration from which a value has been selected by an index.
EnumerationValue: Enumeration value, which is listed in the referenced LexEnumeration.
LexEnumeration
LexEnumeration is an ordered list of values from which a particular value may be selected.
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ISO/PAS 12006-3:2001(E)
EXPRESS specification:
*)
ENTITY LexEnum
...