§ 2.4.1
From Building Product Models to BIM
Thinking in products, rather than processes, has been considered a paradigm shift for the construction industry. Apart from the need for rationalisation and normalisation of processual aspects of construction, analogous efforts have taken place in the area of product-related research. During the 1970s and mid80s, one of the most predominant line of though was dealing with the problem of structuring information
so as to represent knowledge about facts and artefacts (Eastman, 1999, p. 111). This shift naturally followed similar changes in other industries, such as again, the manufacturing and aerospace industries. With initiative from the USA Air Force, product definitions were developed around the mid-80s to support “the direct and complete exchange or sharing of a product model amongst computer applications, without human intervention” (Dado, Beheshti, & van de Ruitenbeek, 2010). These efforts, which coincided with the first efforts for standardisation, aimed at replacing the existing product definitions that were based on graphics and two-dimensional (2D) geometry and were prone to misconceptions and numerous different interpretations from the human agency.
The advancements in product modelling from other industries joined the long- standing debate on the computerisation of AEC (Eastman, 1999, p. 30). Dado et al.
(2010) define a product model as an integrated representation of information and data about an act over its product life-cycle. In the context of AEC industry, the term Building Product Model (BPM) is used to denote the information about a building component embedded in a product model (Eastman, 1999). Nederveen et al. (2010)
differentiate BPM from older technologies as to the potential of the former to be stored explicitly in a formal, computer-interpretable manner, without been susceptible to human interpretation. The origins of BIM are found in various approaches for object- oriented building product modelling that took place in the 1990s (Eastman et al., 2008, p. 354). Essentially BIM authoring applications follow the principles of Object- Oriented Modelling. A massive uptake of BIM appeared in the last decade, although it has been considered an unfulfilled prophecy for more than three decades. During this period, various standards have been developed, eagerly supported, and discontinued. Whereas currently, the terms Building Information Modelling and, its acronym, BIM have been made synonymous with various commercial software solutions for AEC, BIM is essentially an ‘umbrella’ term, similarly to the SCM philosophy. This umbrella term denotes apart from its merely commercial instances, e.g. software applications such as Autodesk Revit, Bentley Microstation, Graphisoft Archicad and numerous more, the process of modelling building products, also known as ‘BIM-ing’, the BIM-based processes in Design and Construction, as well as the outcome of these processes, i.e. the Building Information Model. This sub-section has provided a historical review on BIM from the product modelling efforts in AEC. To understand the future directions that BIM-related research will address in the coming years, a review of its core goals and attributes was performed next.
§ 2.4.2
Exchange and collaboration standards pertinent to BIM
Information exchange standards in AEC
A standard in IT is a set of solutions that aims at satisfying and balancing the needs and requirements from a diverse group of actors in a seamless manner for electronic communication within and between computers (Laakso & Kiviniemi, 2012). The standards are expected to be used “during a certain period, by a substantial number of the parties for whom they are meant” (Vries, 2005). Various efforts took place aiming at creating a standardised model for building product information in construction. The efforts for the standardisation of building information could be considered a form of “horizontal standard,” focusing on achieving compatibility among an array of building product entities (Vries, 2005). While it was beyond the scope of this thesis to offer a comprehensive presentation of all the developed standards pertinent to BIM, only a few seminal and highly relevant to the current and future research directions of BIM have been reviewed. This review of standards underlines their affinity to BIM and the role it could potentially play in the combination of SCM and BIM concepts, as they reappear in the subsequent thesis’ chapters.
The human-derived need to trust the exchanged information as to accuracy and conciseness, and the machine-based necessity for interoperability, motivated the efforts for standardisation. Those were organised from industrial consortia and cross- organisational bodies and began in the 1970s (Björk & Laakso, 2010). The Standard for the Exchange of Products model data (STEP) was the first effort in the AEC industry to combine human-readable graphical information to machine-readable information organised in Entity-Relation (ER) descriptions (Laakso & Kiviniemi, 2012). So far, the Industry Foundation Classes (IFC) standard, which was based on STEP, has been the most long-lived (Björk & Laakso, 2010). The IFC was specified and developed by the international non-profit consortium International Alliance for Interoperability (IAI). IAI is now named BuildingSMART and primarily focuses on standardising the processes, workflows, and procedures for BIM (BuildingSMART, 2014). Thus, the efforts for standardising product modelling information in AEC now shift towards standardising BIM.
IFC is a common language used for transferring concise information among various BIM applications. IFC has so far undergone various revisions, since 1994 (Laakso & Kiviniemi, 2012). The IFC has so far experienced four major versions and a couple of additions (Amor, 2015). Its strategic goals remain unchanged: to represent a neutral and open specification for BIM. Being neutral, suggests that it was destined to be a higher-level data model, above software implementations (Laakso & Kiviniemi, 2012). Being open, suggests that it aims at being exchanged and shared among the various AEC actors beyond system’s dependencies. Thus, it could allow and enable the various
actors to customise their Information System (IS) infrastructure, still maintaining information transparency when collaborating with their partners. Therefore, the goals of standardising IFC- and, therefore, BIM – are aligned with the ideas of managing the information flows in SCM practices among various SC actors.
In practice, IFC presents still some drawbacks. The disadvantages stem from the inherent properties and development of the standard, but also from the actual process of building information exchange. The various versions of IFC have managed to deal effectively with the complexity of its schema, but often this creates semantic implications (Amor, 2015). In other words, IFC could be still described as an ambiguous “weak- (or loosely) typed system” that allows for multiple interpretations of the objects (Venugopal, Eastman, Sacks, & Teizer, 2012). Therefore, focused considerations on semantics could potentially improve the consistency of the information exchanges through IFC (Amor, 2015). After all, Dado et al. (2010) have long awaited the future trends of building product modelling efforts to be found in the emerging Semantic Web standards such as Web Ontology Language (OWL) and Resource Description Framework (RDF) that are based on the concepts of ontology modelling. Towards these directions, also the efforts to define the IFC-based ontologies in both syntactic and semantic levels are found. For example, Beetz et al. (2009; 2014)
and Pauwels et al. (2011) have proposed solutions for translating the IFC standard into OWL language (IfcOWL). All these approaches have the ultimate goal to increase the systems’ interoperability and the semantic adaptation of the IFC so as to integrate further the AEC lifecycle and particularly the Construction and Operation phases. The IFC is not the native model of the various BIM applications. Subsequently, some loss of information often takes place when the actors exchange IFC files that are converted from the proprietary formats. From a holistic inter-organisational – or SC thinking – viewpoint, the IFC promises quite consistent information among the various actors, despite these losses. Practical experiments of data exchange via IFC in the Netherlands have shown that the IFC standard continues to gain popularity among design and engineering teams (Berlo et al. 2012; 2015). An ideal future scenario, to minimise or eliminate the loss of information from one software platform to another, would be when all BIM-related software companies used more compatible native files, but this remains improbable due to the competition of the various software vendors. The IFC remain fairly promising regarding interoperability among the various native files that are used by the multi-disciplinary actors in a project. Given that longevity of the IFC standard is among the key goals of BuildingSMART, its continuous adoption could potentially also support a greater industrialisation of the AEC industry, given that when comparing AEC to the manufacturing sector, the former lacks the penetration of object-oriented product modelling approaches.
Collaboration standards in AEC
Another category of standards pertinent to BIM could be considered the various collaboration standards that emerge and aim at describing the function of BIM implementation, a type of vertical standard (Vries, 2005). For example, Constructive Objects and the Integration of Systems (COINS), which is also affiliated with
BuildingSMART, is an effort since 2003, initiated in the Netherlands. It contains both exchanging formats and prescriptions of collaboration methods or principles of information management (Dado et al., 2010). COINS aims at offering complementary support to the implementation of BIM standards, such as IFC. Further review and analysis of collaboration standards for BIM, fall beyond the scope of this thesis, given that it aimed at investigating the transformations of processes, products, and organisations from the use of BIM and not to primarily focus on standards. Nevertheless, standardisation brings the industry a step closer to integration. In the UK, a PAS (Publicly Available Specification) about BIM collaboration has been developed and revised since 2013. The British Standards Institution (BSI), which issues these PAS, is sponsored by the Construction Industry Council (CIC) and addressed to the various multi-disciplinary organisations of AEC. The PAS suggests a standardised manner to implement a new technology or guidelines and to serve a specific market need. The PAS 1192 consists of many updated specifications over the years. They are usually developed in collaboration with a consortium or other private organisation and are considered a precursor of standardisation. Regarding BIM, the PAS 1192 are considered guidelines to achieve the coveted, yet ambiguous ‘Level 2’ of BIM implementation on all public sector asset procurement by 2016. Like the IFC standard, the PAS 1192 is based on older collaboration requirements in the version of 2007. The PAS 1192-2:2013 specifies information management for the delivery phase of construction projects using BIM. The PAS 1192-3:2014 focuses on the operational phase of assets and offers guidance on the use and maintenance of the Asset Information Model (AIM). It intends to prescribe the collaboration process in BIM- based projects and information management to the various multi-disciplinary actors. Previously, some UK-based researchers have opposed to top-down approaches to BIM and suggested that bottom-up BIM implementation approaches could overcome the resistance to change on behalf of the participating firms, by utilising both the employee’s potential as well as conscious change management strategies (Arayici et al., 2011). It seems that whereas the concept of BIM becomes increasingly relevant, the exact process to implement it is still quite ambiguous, and requires further external and top-down regulation in the UK.
Other specifications of Building Information
Construction Operations Building information exchange (COBie) is a set of data specifications, which includes a data schema and data capturing process. COBie was introduced to illustrate how information from the IFCs could be provided from the designers to the Facility Management (FM) (East, 2007). Subsequently, this specification, which is essentially a spreadsheet translation of the IFC, provides insights into the actors that model the information in the associated lifecycle phases. Also, this specification presents building information in a non-graphical yet highly intuitive and accessible human-readable manner. It this context, COBie could also be viewed as an ”operational standard” (Yalcinkaya & Singh, 2015). COBie is similar to a ‘birth certificate’ of building information and aims to be used during the later stages of the projects for operation or maintenance. The review of COBie was not further continued in this thesis, because, unfortunately, COBie contains information about the generation and not the sharing and exchanging of information, which has been the focus of this study. However, COBie after some usability enhancement could reveal a promising way forward as to the management of Building Information beyond Design and Construction phases, as it is avidly promoted by the PAS specifications in the UK.
§ 2.5
Opportunities for SCM from BIM applications
§ 2.5.1
The adoption of ICT capabilities in AEC
With the advent of technology, solutions from Information and Communication Technology (ICT) are becoming increasingly popular for the management of construction projects. Given that ICT offers tools for making informed decisions, it could manage the project complexity. This thesis reviewed such applications as to their usability for management. The ICT approaches offer informational and analytical tools for assisting the involved actors in a variety of Design and Construction processes, by allowing the access and sharing of information. Among the first application areas of ICT in construction were the graphical and visualisation capabilities, e.g. from Computer-Aided Architectural Design (CAAD), data analysis, information sharing, communication, and collaboration, via numerous Internet capabilities. BIM has been considered such a new type of ICT – or better simply IT, as it generally lacks communication capabilities –, with built-in features of generating and managing building information, e.g. three-dimensional (3D) design, visualisation, automated drawings and codes generation, and quantity take-off.
Construction ICT has focused either on design or management capabilities (Forbes & Ahmed, 2010). For example, past solutions that used ICT for management in AEC focused primarily on exchanging information so as to manage the invoices, quantities, and crews. For communication, most organisations used extranets (Ajam, Alshawi, & Mezher, 2010), ERP, and online project databases for information management. Through these massive IS the actors exchange and share various project documents, such as planning in the form of Electronic Document Management (EDM), orders and invoices in the form of Electronic Data Interchange (EDI) and less often building information, either as printed documents, from CAAD applications or as object- oriented models, e.g. BIM. However, so far no technology has been globally accepted from all the various AEC disciplines both at a document type of the exchanged information or the type of used IS (Samuelson & Björk, 2013; Demian & Walters, 2014; Samuelson & Björk, 2014). Overall, object-oriented, e.g. BIM-based, models have rarely been adopted in the past (Demian & Walters, 2014). BIM offers capabilities for combining both design and management capabilities and thus is inclusive and intuitive.
A variety of IT applications for design and management could be supported by BIM, either from the built-in features of the BIM authoring software or by specialised or customised tools. Cao et al. (2014) categorise the various BIM applications as to the respective phases that are used: design or construction phase. The framework of Cao et al. (2014) has been heavily influenced by Gao and Fischer’s (2008) framework, which categorised the various BIM applications as to visualisation, coordination, and collision detection or avoidance. However, to further analyse the impact of these applications, this study classified BIM applications as to the scope, i.e. their relevant management area. BIM as an IT could support four areas of management in AEC projects: design management, information management, construction management, and performance management:
–
Design management includes the notions of initiation and project scope (and also any considerations for sustainability) and ensuring collaboration among the project team.–
Information management category includes the BIM-based efforts of data and interoperability as well as the need to distribute consistent information to the various multi-disciplinary project actors.–
The aspect of construction management includes all efforts for managing the construction site and maintaining the facility, such as construction site management or FM.–
Performance management entails management considerations that additionally focus on special isolated performance metrics, not applicable to all projects.From the above categories of BIM’s capabilities for the management of AEC, this thesis further emphasised on design, information, and construction management. Given that the overarching research goals relate to the further promotion of SCM in
AEC, no extraordinary building performance considerations were taken into account. At the same time, design and construction management refer more to the material flows of the SC concept, whereas information management relates to the intangible information flows of AEC projects. The capacity and potential of BIM to management these tangible and intangible SC flows were reviewed next.
§ 2.5.2
The potential of BIM in support of the SC flows
Material flows
BIM, being a building product model per se, could support the material, or building product flows during the Design and Construction phases of AEC. During the Design phases, BIM offers various capabilities for updatable and consistent quality management and quantity take-off calculations of the materials to be used in a project
(Eastman et al., 2008). The material capabilities of BIM start from the potential for quality management, by comparing and ensuring the compliance of the selected material to the project specification requirements and the construction codes (Chen & Luo, 2014). The object-oriented logic behind BIM could not only automatically produce the Bills of Quantities for the project, but also dynamically enrich it with model properties (Eastman et al., 2008). Therefore, BIM could support the material flows, even before they are procured and placed on the site. This possibility of BIM could play the role of transferring the site activities to the SC, as described by Vrijhoef and Koskela
(2000). Subsequently, the preparatory activities on the site have the potential to start before the actual delivery of materials.
During the Construction phase, the object-oriented capabilities of BIM could be used to support various site activities, such as the transportation of the materials, their distribution on site and the optimisation of the construction site layout. BIM combined with the use of mobile technologies could develop and maintain feedback mechanisms between the design and construction teams (Irizarry, Karan, & Jalaei, 2013). Simultaneously, BIM could monitor the supply chains by integrating tracking technologies, such as barcodes, RFID, and Global Positioning System (GPS), to enhance the visibility during the material delivery (Irizarry et al., 2013). Other BIM applications for the material flows concern the control and optimisation of the construction site layout, by linking BIM to algorithms for automated site storage planning (Kumar & Cheng, 2015). Concerning the flow of equipment on sites, coupling BIM and GIS technologies, could support the decision-making process for the layout of construction equipment on site (Irizarry & Karan, 2012). Therefore, technologies such as mobile, GIS and RFID could be combined with BIM to regulate and optimise the material- related flows of the SC and contribute to SCM applications such as integrated
operations, logistics control (Vrijhoef,2011). Ergo, BIM has the potential to act as a multi-faceted integrator of various technologies and processes for the monitoring and the control of material flows in the construction site.
The material flows are considered a downstream flow of the digital and physical materials on the construction site. At the same time, there is a highly associated flow to that, which concerns the cash flows of the materials. BIM is used for calculating the cash flows after automatically extracting the Bill of Quantities and strengthening the feasibility and control of project cost analyses. After all, the project benefits of BIM include cost reduction, given that enhanced control and time savings could be observed by applying BIM to these processes, according to Bryde et al. (2013). Forgues et al. (2012) claim that the cost estimating methods have changed enormously after