Methods and Techniques for Integrating Computer and Information Technology Applications towards Computer Integrated Construction (CIC) #

 

T.V.S.R.Apparao* and V.Laxmi Narasaiah**

 

 

ABSTRACT:

 

It is well known that integrated use of computer and information technologies would only improve the productivity in construction. The aim of this paper is to discuss the various problems and issues relating to the present mode of usage of computers and IT and to present briefly the efforts being made towards integration, leading to Computer Integrated Construction (CIC). The advances being made in   efficient information modeling and data exchange standards in creating an integrated environment will be discussed in this paper. Methods/techniques/tools for integration, such as object-oriented modeling, databases, product and process modeling standards, 3D modeling, virtual reality, and AI techniques including knowledge based expert systems will be discussed briefly in this paper. Suggestions are made for future research and development in this area and to improve the productivity in construction in India.

 

INTRODUCTION

 

Construction of facilities accounts for a significant part of capital expenditure particularly in developing countries like India. Therefore, improving productivity with safety in construction is of great national importance. Quality, productivity, and speed are the main aspects or parameters that need improvement in construction. Computer and information technologies can play a significant role in this regard and the present situation can be improved, by using/developing methods/techniques for integrating their application.

 

Construction as a whole is a complex task involving architectural planning, engineering design, and the construction process (AEC). Different professionals namely architects, engineers, contractors, financiers, material manufacturers/suppliers and others have to interact closely to complete the project on time and within the budget while meeting established quality requirements and other specifications. This interaction involves large-scale exchange of data/information, including engineering drawings, specifications, and reports (relating to different facets of design, construction and maintenance throughout the lifecycle) through discussions and communications among the parties concerned.

 

Civil structural engineers are among the pioneers in making use of computers initially to solve some of the large/complex and computationally intensive problems of structural analysis starting in early 60s. Considerable developments have taken place during the last

________________________________________________________________________ *Emeritus scientist [CSIR], **Junior Research Fellow, Structural Engineering Research Centre (CSIR), Chennai-600113.

# Paper to be presented at the IBC seminar, November 2003, at Bangalore

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four decades in the development of computer software for application in different specialist areas of the AEC life cycle process [1-4]. It can be seen that the computer applications are fragmented in nature [5], since they deal with specific /individual problems such as architectural layouts, cost estimation, structural analysis and design, detailing, construction planning, scheduling and management, etc. Information technology is presently   being used mostly for communication of textual (specifications, reports, letters/documents, etc.) and graphical (architectural layouts, and engineering drawings, etc.) information electronically [6]. Since application software packages used by the AEC industry partners belong to different developers/vendors, data formats used in software applications differ posing problems for data exchange and interoperability. This has been the concern of many researchers and professionals in the industry since software applications are not integrated for realizing the full benefit.

 

Major efforts have been initiated in 1980s for developing methods/techniques for integrating computer and information technology applications towards Computer Integrated Construction (CIC). Data/information sharing/exchange among different parties regarding products and processes in design, construction, and maintenance phases of the project are the main issues that have been addressed by many researchers in academic institutions and the industry as well [7-16].  Towards this, efforts have been made to develop standards for data exchange and for information modeling of products and processes.  This paper gives a brief overview of the standardization efforts started by International Standards Organization (ISO) around 1984 towards development of STEP (Standard for exchange of product data)[9].  It also gives a brief account of the standardization efforts of IAI (Industry Alliance for Interoperability) [10] towards development of IFC (Industry Foundation Classes).  Major projects on information modeling of products/projects have been taken up in Europe, USA [11] and other countries as a step towards CIC. Semantic (meaningful) representation and object-oriented approach   have been used in information modeling since they have been found to be most appropriate/effective for integration.  Use of object-oriented   methodology and product/process modeling standards, along with   3-D modeling, knowledge-based expert systems and AI techniques are being used for project information modeling and integration. An overview of recent developments in the area of modeling and methods/techniques for integration is presented in this paper.

 

FRGMENTED NATURE OF COMPUTER AND IT APPLICATIONS

 

In spite of considerable advances made in computer and information technologies, application software development has been fragmented in nature requiring significant amount of professional judgment and interfacing during the total process of planning, design and construction of facilities. Computer applications have focused on automating individual engineering tasks, i.e. creating islands of information.  The communication protocols that do exist (e.g. DXF, IGES) allow the transfer of low-level data but are often ineffective in bridging between the islands of information. It is well accepted that only through integrated automation of design and construction process can the quality and productivity of the AEC industry improve.

 

PROBLEMS AND ISSUES RELATING TO INTEGRATION

 

Surveys have been conducted in different parts of the world to understand the mode and extent of usage of computers and information technology and its impact on the performance of the construction industry. Reports on the analysis of these surveys highlighted the importance of integration of different computer applications and IT for sharing of information among different teams during life cycle of the construction project. It has been observed from the responses to different surveys that there are some generic/key factors that have prevented the AEC industry to achieve integration of computer and IT applications.  These are:

 

  • Fragmented supply chain
  • Lack of industry standards for information exchange
  • Poor cross-disciplinary communication:
  • Poor knowledge management at industry, enterprise, and project levels

 

Based on several surveys/studies in UK, it was concluded in Egan’s report that the solution of the above problems lies in the integration of the processes throughout the construction supply chain, which helps in saving time and project costs. Teamwork and communication have been recognized as the two major aspects of business process engineering

 

MODELS FOR INTEGRATION

 

The purpose of integration of computer and information technology applications is to facilitate fast communication/exchange of data/information among all the players in the project supporting collaborative/concurrent engineering so as to save time and to obtain optimal solutions. Any building construction project may be conceived broadly to consist of products and processes. Materials, building components, equipment, the constructed facility as a whole, etc. fall under the category of products. Planning, design, construction and all other related activities including scheduling/control fall under the category of processes.  Standards are being developed for modeling of   data of products and processes for facilitating exchange/sharing among the project participants. .

A product model (Fig. 1) is basically a conceptual structure and it implicitly contains data regarding form, function, and behavior of a product (in a neutral format) and is able to describe the product through its lifecycle. With the definition of product model given above, the standards seek to capture the project information in a semantical (meaning full) way. From such semantically rich information model, other models like a geometric model or a FEM model can be derived automatically, and 2D-drawings and other documents could be generated from the same product model. Similarly, processes can be modeled in a neutral format to facilitate data exchange/sharing. Currently integrated information models of engineering and construction of projects are being developed based on standard product and process models. The present trend is towards use of object-oriented approach for developing integrated project information models. Further details about these methods/aspects are presented in the later Sections of this paper.

 

Fig. 1. Product Data Interchange (electronic: PDI)
 

 

 

Different application software packages or “agents” (for design and construction) have been developed (historically) by different vendors, and they all have their own particular data format. To integrate the existing application packages, a mapping mechanism to exchange data is required between the applications. Given the large number of applications used throughout the building construction life cycle, it is impractical to setup one to one mapping between all of them. An Agent-based Framework model may be adopted to create an integrated environment through a Facilitator as shown in Fig.2. The Facilitator may be developed using knowledge-based systems or AI techniques.

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Methods / TECHNiques FOR integration of computer and it APPLICATIONS

 

At present the collective ‘body’ of information about a construction project is mostly communicated via paper documents, individual files from a wide range of computer applications, engineering drawings, and through discussions/conversations among the project participants. Even though the construction industry is heavily information based, it may lag other industries in its rate of adopting methods/techniques, offering great potential for improving information processing and management practices, communication, and finally for improving the interoperability with out changing its basic premise. The following are the important methods/techniques for information processing and management and they can be effectively used in developing integrated computer and IT application environment towards Computer Integrated Construction (CIC):

 

Ø     Object oriented modeling

Ø     Product & process modeling standards

Ø     Integrated databases

Ø     3D modeling & Virtual Reality

Ø     Communication standards for collaborative work

Ø     Artificial intelligence techniques

 

Object Oriented Modeling

 

Object-oriented modeling (also known as object oriented technology, or object orientation) is a new way of thinking about problems using models organized around real world concepts.  The model contains objects found in the application domain such as design and/or construction of a facility. Models are represented by diagrams called schemas. Object model schemas show the object structures and event model schemas show what happens to objects. Each object combines both data structure and behavior in a single entity.  The object-oriented model describes the structure of objects in a system - their identity, their relationships with other objects, their attributes, their operations, and resulting events. In contrast to the commonly adopted functional methodology, object oriented approach focuses on identifying objects from the application domain, then fitting procedures around them.

 

Using object orientation as a base, a system is modeled (the word ‘system’ is used here with a wide meaning and can be either a dedicated software system or integrated software and hardware system or organization) as a number of objects that interact. Hence irrespective of type of system being modeled, its contents are regarded as a number of objects, which in one way or another are related. For instance any construction facility will be consists of objects (like deck slab, girder, bearing, pier, and foundation in case of bridge) rather than low-level primitives (like points, lines, edges, and etc.). Thus what the object model depends on what one wants to represent with the object model.

 

People regard their surrounding environment in terms of objects. Therefore, it is simple to think in the same way when it comes to designing a model. A model which is designed using an object-oriented technology is often easy to understand, as it can be directly related to reality. Thus with such a design method, only a small semantic gap will exist between reality and model.

 

Object-oriented systems holds up better as requirements evolve, because it is based on the underlying framework of the application domain itself, than ad-hoc functional requirements of a single problem.  Object oriented development is a conceptual process independent of programming language until the final stages. One important advantage is that the objects are reusable within other software systems.

 

The key elements of the object-oriented approach, making it different from the conventional approach, are abstraction, encapsulation, inheritance, and polymorphism.

 

The object-oriented modeling approach has been embraced in almost every area of IT and construction. This ranges from object-oriented modeling (e.g., development/ adoption of product and process models), to object-oriented programming (e.g., C++, JAVA), through to object based CAD systems (e.g., ArchiCAD, Architectural Desktop, ProReflex, MicroStation TriForma, etc). The object-oriented modeling also has been adopted as a development methodology in research and development projects dealing with integration, product and process modeling, information exchange and other initiatives (including CIM Steel, STEP, IFC, WISPER etc.).

 

Product and Process Modeling Standards

 

Development of product models and industry data model standards for product models such as ISO Standard 10303, STEP [9] and the Industry Foundation Classes (IFC)[10] has been the emerging trend in the construction industry. It is well known that the technologies to create and work with product models have matured significantly and product models are successfully being used to support some applications in manufacturing industries. On the other hand, product model based applications and data exchange have not yet entered mainstream use and many unresolved technical difficulties remain in the AEC industry.

 

Product and process modeling technologies, combined with the attitudes embodied in production engineering, could lead to an exiting new application area: process design tools. Currently, scheduling software probably comes closest to a tool for helping construction process. However, construction process design involves detailed knowledge of the building being constructed, information about available construction methods, and many other types of information that are not included in any scheduling software but that are central to the integrated product and process model approaches.  A new type of process design tool would allow users to explore and inter link a wide variety of construction project information, together with process design and analysis tools such as 4D CAD (3D geometry plus time), to engineer efficient construction process plans. These new process design tools could be incorporated within scheduling, estimating, and CAD tools. A brief description of the standardization efforts of STEP and IFC in product and process modeling is given in the following.

 

ISO (10303) STEP

 

By 1984, the issues of CAD data translation suggested to a number of industry based research groups in Europe and the US that the time was appropriate for a new generation of standards effort. In the US, the new effort was centered around the Product Data Exchange Standards (PDES). About the same time, the International Standards Organization (ISO) in Geneva, Switzerland, initiated a technical committee, TC184, to initiate a sub committee, SC4, to develop a standard called STEP (Standard for Exchange of Product model data). The full title of the standard is ISO10303-Industrial Automation systems-Product data representation and exchange. After initially operating as parallel but separate activities, the PDES and STEP efforts merged in 1991.

 

Industry Foundation Classes (IFC)

 

The lack of integration between different AEC application systems has become the barrier for the wide use of these systems. To address this issue twelve companies involved in the AEC and Facility Management (FM) industry, many of whom are software developers started the International Alliance for Interoperability (IAI), is a voluntary organization created in 1995, to represent the public and private sectors in an effort to facilitate the dynamic exchange of dynamic information among all applications and platforms serving the entire building community throughout the lifecycle of facilities. Within a few years it came to be an international movement counting over 600 members worldwide. The organization’s objective is:

 

§       To develop and recommend practices for the uniform transmission and sharing of information and data.

§       To provide a forum to promote the use of recommended standards of information sharing.

§       To develop a process for certifying compliance with the recommended standards.

§       To implement and foster use of those standards.

 

In essence IAI is another data modeling initiative and collection of classes i.e. Industry Foundation Classes (IFC), which plans to specify classes (for the “things/objects” occurring in the building environment) in a standardized and object oriented way for exchange of intelligent AEC related objects among CAD systems. The initiation of IFC will be to the things that could occur in a construction facility (including real things such as doors, windows, walls, fans, ceilings etc. and abstract concepts such as space, organization, process, schedule activity etc.) what DXF standards to graphic entities (like points, lines etc.).

 

Integrated Databases

 

An engineering database (often called CAD or CAD/CAE database) is one of the components of computer integrated construction systems. Since CAD/CAE packages and network facilities have allowed interactive sharing of design information as well as data transfer, the engineering database became the most important resource of an engineering firm. The design product (and its data) continuously evolves during such a process. As a result, construction design data is very different in comparison with a conventional database for the following reasons:

 

  • Construction design data are characterized by many different types of components.
  • Design data records are long, with a variable length of textual information and compared to short, fixed length classical databases
  • Temporal and spatial relationships are unique and important in design data representation.
  • Design changes and updates are not predictable and are likely to affect many components or construction elements; these updates are very difficult to automate.
  • There is a high level of duplication of design data, especially between architects, structural designers, HVAC designers, and others.
  • Design management and coordination is complex and different from project to project.

 

It is well known that an integrated construction project database (project model) [7] is highly desirable for computer-integrated construction and vital for facilitating effective communications between project team members and between the stages of the project life cycle. The trend is toward developing object-oriented databases for this purpose.        

3D Modeling and Virtual Reality [17]

 

3D-CAD is a well-established technology that is beginning to enter mainstream use. One significant aspect of 3D-CAD is that it has established the role of using computer based “building models” for design and construction. This introduces a natural progression towards increasing semantic information (i.e., CAD entities modeled as specific building components rather than generic shapes) and increasing non-geometric information in the CAD models-that is towards use of building product models.

 

The construction industry must see now transition from paper or electronic drawings to 3D modeling to realize the following benefits:

 

§       Any number of drawings could be automatically obtained – sections, isometric (or) perspective projections from a 3D model. All drawings extracted from same 3D model were guaranteed to be consistent with each other.

§       Automated computation of quantities for cost estimates and bills of quantities

  • A 3D model can be used in many ways that a drawing could not. Among the many uses are 3D visualization (animation and walk through etc.), and as input to various forms of analysis, which are not possible from a digital drawing representation. 
  • Visualization of construction process by incorporation of time dimension (4D CAD) into the concept of 3D Visualization.
  • Improving facility management

 

Virtual reality is one of the advanced computer graphic technologies dealing with visualization. Like the telephone, virtual reality (VR) is a communication medium, but it is also a tool for looking at information. Virtual Reality Modeling Language (VRML) is a generic language designed to allow three-dimensional objects to be depicted and for simulation. VRML files describe the 3D-space in a standard text like format, which is interpreted by browsers. As a result, if we have an appropriate 3D-viewer (or VRML browser) we can view and interact with the 3D model of design or virtual environment. A VRML world is made up of simple shapes such as cubes, cones, and shapes grouped together to form more complex objects.

 

Artificial Intelligence Techniques [18]

 

Mainstream computer applications have greatly performed over humans in the areas of accurate and high-speed numerical input, processing, organization, and retrieval of vast amount of information. However, this is not the case when expertise and experience are required for finding the solutions, especially in planning and design. Artificial intelligence is one of the computer sciences that attempt to replicate non-numerical reasoning process, which have been until recently considered inherent only to humans. Artificial intelligence does not attempt to enact human thinking process, but utilizes computer tools to approximate human (expert) behavior. Today AI based systems are used in a number of areas, such as diagnosis, speech processing, natural language processing, games, image processing, and robotics. However, AI technology has a notable significance for the areas employing complex heuristic (experimental based) knowledge such as civil engineering. Among the most applicable traditional AI techniques (including knowledge based systems, machine learning, and planning), much of the research in AI has concentrated on problem solving. Knowledge based system (KBS) is one of the most powerful problem solving technique of AI, and one of its most applicable versions is - the knowledge based expert system (KBES). AI application in design and construction can provide important capabilities including automation of routine design, incorporation of expertise and standards, support for decision making, and checking against company and industry standard.

 

MAJOR DEVELOPMENTAL EFFORTS Towards computer integrated construction (CIC)

 

Research and developmental efforts towards realizing Computer Integrated Construction have addressed the problem of integration (either partly or fully) by adopting a variety of ways:

 

  • Communication between applications, achieved through integration of   chosen  software applications (either through file transfer or agent-based approach)
  • Integration through geometry, often the case in commercial CAD packages where integration is based on and limited to geometrical information
  • Knowledge based interfaces linking multiple applications and multiple databases, and
  • Integration through central project databases holding all the information relating to a project according to a common infrastructure model.
  • Using product and process modeling

 

Many major developmental projects taken up during 1990s fall mainly under the later category and make use of object-oriented modeling and adopt standards for data exchange. These include projects such as CIMsteel [8] (for computer integrated manufacturing in steel for building framed structures), RATAS [13]  (for building design and construction management), and WISPER [14] (integrated environments for building design and construction), and USACERL [15](integrated information model for design and construction). The salient features of these projects have been presented in the report [19] brought out by the authors.

 

FUTURE DIRECTIONS

 

The present trend clearly shows that computer and information technologies will find increasing applications world-wide in future in the total life cycle processes of planning, design, construction and maintenance of civil infrastructure facilities.  Efforts will be directed towards development of integrated applications leading to computer-integrated construction (CIC) to increase the efficiency and to save time and cost besides improving upon the safety and quality.

 

Building product models and industry data model standards (like IFC) have been engaging researchers and the industry for some time now and these will be used widely in the future.  Several trends within the construction industry - Process Re-Engineering, Total Quality Management and Lean Construction - focus on better engineering of construction processes. This will lead to process modeling and working with information about construction work processes. Innovative process design tools would allow users to interlink a wide variety of construction project information [20], together with process design and analysis tools such as 4D CAD (3D geometry plus time).

 

Increasingly the internet will be used for distributed systems and generic data exchange (using technologies like XML).  These technologies together with data model standards will lead to more industry-specific data-exchange technologies and to increasing levels of software integration.

 

All project information will become accessible via web browser and can be shared between project participants and project stakeholders subject to the requirements/permissions.

 

The above mentioned vision of developments in computer and IT applications will facilitate life-cycle thinking with seamless transaction of information and processes between life-cycle phases. Information technology together with use of databases and AI techniques will enable the use of past knowledge in construction for new projects

 

The increased use of the Internet opens new business opportunities for construction organizations such as Project Information Exchange, e-Tendering and web-based services. This will bring out dramatic changes in procurement philosophies such as just-in-time procurement, and will lead to integrated supply chains. The future emphasis on integration will be process-centric providing a clear-cut business case that appeals to the executive management

 

CONCLUDING REMARKS

 

It is well known that integrated use of computer and information technologies would only improve the productivity in construction. Efficient methods/techniques of modeling and standards have to be adopted for exchange/sharing of data/information relating to different applications in engineering and construction of projects. An overview of the advances being made in this area is presented in this paper.

 

In order to improve the productivity in construction, the AEC industry and the related regulatory authorities in India may take immediate steps to:

 

q      Develop/ adopt data/information exchange standards for products and processes relating to design and construction of facilities.  AEC organizations, Bureau of Indian Standards (BIS), research and academic organizations may   take part in the standardization efforts of ISO and IAI.

q      Develop databases (electronic) relating to materials, products/components, methods/processes, costs, productivity, etc. Designers and the construction industry will be benefited if these are available through computer networks. Databases of completed projects would help in maintenance of facilities and in efficient   planning/design of future projects

q      Make efforts to develop/adopt   object-oriented application software for enabling creation of integrated software environment. Attempts have to be made to create integrated databases for projects using standard product and process models.

q      Evolve methods/procedures for facilitating the use of information technology in all activities of the life cycle process of construction (tendering, contracting, designing, approving, procurement, construction, billing, payment, etc) and   maintenance of facilities, and to use computers and IT in an integrated manner.

 

 

ACKNOWLEDGEMENTS

 

The authors are thankful to the support provided by Council of Scientific and Industrial Research (CSIR) for carrying out R&D studies in the area and to prepare this paper.  They would also express there thanks to the Director, Structural Engineering Research Centre (SERC), Chennai, for his constant encouragement and support.

 

 

 

 

REFERENCES

 

1.     Retik, A., and Langford, D., Computer Integrated Planning and Design for Construction, Thomas Telford, 2001.

2.     Fruchter, R. (Editor-in-Chief), Computing in Civil and Building Engineering, Proceedings of the Eighth International Conference, ASCE, Vols. 1&2, Stanford University, Stanford, California, Aug 14-16, 2000.

3.     Appa Rao. T.V.S.R, “ Trends in computer application and use of information technology for design, construction, and maintenance of infrastructural facilities”, Journal of Indian Building Congress, 9(1), 41-48, 2002.

4.     Information Technology for Construction Industry, Special Issue of The Indian Concrete Journal, Vol.74, December 2000.

5.     Howard, H. C., Levitt R.E., Paulson, Jr. B.C., Pohl G., and Tatum C.B., “Computer Integration: Reducing Fragmentation in AEC Industry” Journal of Computing in Civil Engineering, ASCE, 3(1), pp18-32, 1989.

6.     Appa Rao, T.V.S.R., Laxmi Narasaiah, V., “Use of Computers and Information Technology by the Construction Industry in India - Assessment of Present Status and Needs”, Report No.01-03, Project – EMR 0141, SERC, Chennai, Feb 2003.

7.     Teicholz P. and Martin F., “Strategy for Computer Integrated Construction       Technology", Journal of Construction Engineering and Management, ASCE, 120(1), pp 117-131, March 1994.

8.     CIMsteel, http://www.cae.civil.leeds.ac.uk/past/cis/cis.htm.

9.     The STEP Project, http://www.nist.gov/sc4/www/stepdocs.htm.

10.  International Alliance for Interoperability, http://www.iai-international.org/iai_international/.

11.  Computer Integrated Construction Group, http://cic.nist.gov.

12.  Watson A.,”Integrated manufacturing of construction in steel - Exchanging data through the product life-cycle”, http://www.natspec.info/Toolbox/AboutCIS/R&D/Intmanst.pdf.  Bjork

13.  B.C.,”RATAS Project - Developing an Infrastructure for Computer Integrated Construction”, Journal of Computing in Civil Engineering, ASCE,8(4), pp 401-419, 1994.

14.  Faraj I, Alshawi M, Aouad G, Child T, and Underwood J.,”An Industry Foundation Classes Web-Based Collaborative Construction Computer Environment: WISPER”, Automation in Construction, 10(1), pp79-99, 2000.

15.  Stumpf A.L., Ganeshan R., Chin S., and Liu L.Y., ”Object Oriented Model for Integrating Construction Product and Process Modeling”, Journal of Computing in Civil Engineering, ASCE, 10(3), pp 204-212, 1996.

16.  Fischer M., Kunz J., “The Circle: Architecture for Integrating Software”, Journal of Computing in Civil Engineering, ASCE, Vol 9, No.2, pp122-133, April 1995.

17.  Kunigahalli R., “3D Modeling for Computer Integrated Construction of RC Structures”, Journal of Computing in Civil Engineering, 11(2), 92-101, 1997.

18.  Sriram D., and Adey R., (editors) Proceedings of the 1st International Conference on Applications of Artificial Intelligence in Engineering Problems, Southampton University, UK, Computational Mechanics Publication, April1986.

19.  Appa Rao, T.V.S.R., Laxmi Narasaiah, V., “Developments in Computer and Information Technology Applications towards Computer Integrated Construction (CIC)”, Report No.02-03, Project – EMR 0141, Chennai, SERC, June 2003.

20.  Froese T., “Interwoven Threads: Trends in the Use of information Technologies for the Construction Industry”, A white Paper Prepared for the Berkely-Stanford CE&M workshop, August 1999.