BUILDING INFORMATION MODELLING:
AN OVERVIEW OF THE PROCESS FROM AN IRISH CONSTRUCTION PROJECT MANAGEMENT PERSPECTIVE
By Paul Stewart
The construction industry in Ireland and across the globe has not matched other sectors increases in productivity over the years. In fact, data in the US shows it has actually declined since the 1930’s. The construction industry is notoriously conservative and slow to change. Many of the same traditional procurement and project delivery formats have remained the same for decades. The aim of this journal article is to give the reader a brief overview of Building Information Modelling (BIM) to allow construction managers gain an understanding of its potential as an integrated project management tool and how its implementation into construction projects could help productivity. The paper identifies key areas of BIM and discusses their uses. It investigates the use of BIM technologies as a collaborative means of producing construction projects from inception, through planning, design, construction and finally completion. The paper identifies the stakeholders required for a collaborative process but places particular emphasis on the benefits to construction project management in areas such as scheduling, safety, constructability and control. These areas are expanded and allow specific professions to understand the interrelationship between all professions and the obvious advantage of working together.
The article relates the use of BIM to the current Irish construction industry, its current practices and some of the barriers which are in the way of increasing productivity within the industry. These include tradition, the conservative and fragmented nature of the construction industry, education, legal barriers, conflicts of interest, expense and the speed of change of available software’s. Just as it is impossible to be an expert in every profession, it is also impossible to become an expert in all areas of the BIM process. This is why an overview of the process shown in an Irish context with an emphasis on project management is so important to the industry at present. If BIM is only seen or investigated for its individual uses to each procession and not viewed in a holistic manner, a huge proportion of its potential to increase productivity in a very unproductive sector will be lost.
Keywords: BIM, Visualisation, 3D, 4D, 5D, Constructability, Collaboration, Clash Detection,Safety, Quantity Surveying, Productivity
“Building Information Modelling (BIM) is a digital representation of physical and functional characteristics of a facility. A BIM is a shared knowledge resource for information about a facility forming a reliable basis for decisions during its life-cycle; defined as existing from earliest conception to demolition. A basic premise of BIM is collaboration by different stakeholders at different phases of the life cycle of a facility to insert, extract, update or modify information in the BIM to support and reflect the roles of that stakeholder” (National BIM Standard - United States)
This article is a first stage exploratory piece of work into the functions and uses of BIM and there potential benefit to the Irish construction industry. BIM is currently not utilised in Ireland and is not understood. This work is an attempt to gather existing information and present it in a way which canhelp the industry to understand BIM in its broadest context and to highlight the need for continue research into specific areas by the differing professions within the industry.
The review of the literature allows the reader understand the complex nature of the BIM process. The paper does not attempt to answer all the questions about the BIM process in Ireland but rather acknowledges that BIM in its true form does not exist. The paper tries to pre-empt where the areas of further research will lie in the near further and identify areas of particular interest to many within the industry.
| Currently broad explanatory or exploratory review of BIM in an Irish context exists. This paper can be a means of creating debate and encouraging the requirement for considerable continued research into this very large topic. |
BIM has the potential to change forever and make redundant all previous methods of construction project delivery. The most common traditional means by which projects have generally been delivered in Irish state has not changed since its foundationand was used long before this in the UK and other countries also. The lack of current knowledge in the Irish industry may hamper the speed by which this change may take place.
The paper first briefly explains and explores all the current uses of BIM under single individual topics. Unlike previous MPM research papers, this dissertation paper has been designed to follow the layout of a journal article. Due to the broad nature of the topic and its intended aim to give an overview which can help an entire industry gain a broad understanding of BIM, it does not focus on specific areas in considerable detail. It does however, allow the reader, appreciate the wide ranging compass of BIM and direct them toward areas they believe would be of greatest benefit to them without losing sight of the overall holistic approach required to gain full productivity from the BIM process.
To this end, mainly articles from the 2007 on were studied in greater depth during the later stages of the literature review. Notes were compiled on a broad range of articles, journals and books and a literature review grid of common points was produced. These common points became the basis for the headings under which the article would be structured. This was the ideal manner to ensure that the major points and areas under which BIM was used could be discussed and information imparted to the proposed audience and to allow direction as to what future research will be required to help the Irish construction industry utilise BIM.
To date, many BIM articles simply did not appear to give all professions a good overview or understanding of BIM in its broader sense. The process was discussed under the following headings:
• Clash Detection
• Quantity Surveying/5D
• Progress Tracking
It became apparent from the common points grid which areas had been discussed in detail and which points appeared to have a gap in study into them. To keep the paper to the concise journal article type length proved most difficult and this paper reached the higher limits. It also became apparent that the current construction project delivery methods in Ireland had led to less than harmonious relationships between many of the stakeholders and that BIM’s potential to aid the entire procurement and delivery process was likely to become a future issue within the industry. Project alignment and Delivery are also discussed in both the main body and the conclusions.
Visualisation From the earliest adaptation of BIM or even simple 3D modelling, it was apparent that the visualisation aspect allowed designers, owners and contractors see and comment on construction projects prior to them starting onsite. In this most basic form, it gave the stakeholders an opportunity to add or remove components they liked or disliked without incurring the same costs as they would have had during construction stage and without the same possible delay consequences. However, perhaps more importantly, it allowed on-site teams view the expected outcome and understand far more quickly what the designer expected to be built. This essentially allowed many teams on complex projects hit the ground running. As recently as 2006, many considered BIM’s primary attraction as the ability to animate designs. In a case study covered in an eminent journal at that time, it was noted “The initial and primary motivation for developing the 4D schedule was to enable non-technical senior stakeholders, who would approve the project, understand what the scope of the project was” Basu (2007).
| It would of course be foolhardy not to see the merit in 4D as a visualisation tool, but in truth, it has been oversold as one of the major benefits of BIM. It has been used as a marketing tool to win contracts and frequently never used for its many other attributes. Again, much of the reason for the over emphasis on the visual aspects of 4D models up until the late 2000’s could be attributed to the available software and the difficulty in using it. Thus, BIM tended to be used only on larger projects where expertise could be employed on a full time basis. Visualisation was cited as a major contributor to the understanding of stakeholders, particularly sub-contractors on the construction of the Benjamin D. Hall Research Building, University of Washington, a complex facility. The visualisation of sequencing allowed sub-contractors see clearly where they fit in to the workflow. |
‘Computer Advance Visualisation Tools’ (CAVT) (Rischmoller et al. 2006) concluded a case study which showed CAVT resulted in reduced waste, improved flow and better customer value. This cannot be attributed solely to the visual model but must also take into consideration some of the other tools implied and discussed later on. However, the study did show it was of significant effect. Sacks et al (2009) discussed the potential contributions of BIM to visualisation of the product and process aspects of construction projects in terms of lean construction principles.
Nevertheless, the benefit of visualisation remained hampered by the software and the lack of expertise available. (Benjaoran and Bhokha, 2009) noted that visualisation was able to eliminate the many different interpretations people may have had with simple 2D drawings, This lead to the ability for those involved to see omissions and evaluate accessibility within the building site.
The advancement of much of the software allows much greater means of visually representing time in BIM models. Frequently, programmes allow colour coding of building components to show what stage they are at on any give date. For example, green could indicate work in progress but not completed, whilst normally the proposed final colour of the component in question indicates it is an activity which is completed. Often a semi transparent third colour representation is added to indicate planned work vs. actual work completed. In addition to this, graphics, animations, annotations and text can be added to video schedules offering greater visual experiences. This can be a very “enlightening information medium” particularly for the non-construction stakeholder (Benjaoran and Bhokha, 2009). However, there are some drawbacks to this visual medium – it is hard to show the relationships and interdependencies between work activities or tasks. A Gantt chart can show these clearly with line and arrow links. Duration is also more difficult to show in animation models whilst progress tracking can give a unique visual view of a project at any given time, the visual aspect is not a sufficient means on its own to be considered a full progress tracking
solution which would drive correctitive actions.
In the Homan high speed railway project, (Cho et al. 2011) explain the benefit of a visual model as a public relations tool. In large scale projects, it is common for the public to have a fear of the unknown. This is often borne out of a lack of understanding and knowledge of a project and its perceived impact on the locality. Visualisation helped the local population understand more easily the processes which were to be undertaken. This proved to be invaluable in getting stakeholder buy in to the project.
From an educational perspective, (Peterson et al. 2011), advocated the visualisation of a construction project as a good means of explaining a project to students in the construction field. It should be noted that many students will have spent little or no time on a construction site and so this simulation could lead to rapid understanding of some of the problems given to students by their tutors.
| Finally, visualisation can be used as a basic means of looking at the sequencing of activities in relation to temporary structures, plant and temporary supports. For example, the digging of external pipe work may not be possible due to the proximity of scaffolding or temporary site accommodation at a particular time during a project. The visual benefits of BIM using 4D scheduling are not the most important aspect of this process, but can still offer significant help in defined areas and tasks. |
“The optimum use of construction knowledge and experience in planning, design, procurement and field operations to achieve overall project objectives” Construction Industry Institute (CII) definition of constructability.
Basu (2007) understood the preconstruction benefits of using 4D scheduling. He noted its particular help in complex phased and live construction site. In fact, whilst perhaps over stated, the case study suggested the “project could not be done without the initial detailed planning and buy-in using the 4D model”. However, there is no doubt that even in 2007 with considerably inferior and more expensive software, it was becoming increasingly obvious that BIM could help in making the construction of complex projects more efficient.
“Virtual Construction” (McCuen 2008) facilitates improvements during the development phase of the project. The knowledge the professionals bring together in producing the 3 & 4D models help during the constructability review. This includes suggestions from all team members. Perhaps insitu concrete may be cheaper to buy, but steel may be significantly easier to construct certain structures in.
(Wickersham 2009) “ Both the architect and the CM will work more intensively prior to the creation of construction documents, and they will share information more freely with each other throughout the process, in order to test the cost and constructability of design.” This process includes the use of 4D scheduling but also refers to the use of an integrated project delivery (IPD) approach. This approach advocates the sharing of risk and reward among the project team. But even without IPD, the BIM process lends itself to constructability reviews.
Perhaps one of the most obvious constructability tools is that of running several alternative designs and testing their constructability utilising the scheduling of the differing components of the designs. The relative ease of this process in comparison to the previous 2D process is staggering. It also allows designers and contractors prove the validity of some of their assumptions without having to learn from physically constructing them or from previous mistakes.
The 4D CAD model is a powerful tool for analyses and decision support (Benjaoran and Bhokha, 2009). They go on to list many of the same topics which have been previously discussed under visualisation and will be further discussed under the proceeding headings, showing the integrated nature of the BIM process. “Topics such as time, working space, sequences and temporary structures” which are all part of constructability reviews. These topics are further explored by (Akinci et al 2002) and (Ma et al 2005)
It has long since been appreciated that constructability can lead to a greater return on investment. In fact, the business roundtable reported a potential saving of up to 10:1 by applying constructability. “The idea was to minimise the gap between what designers draw and what contractors execute on site” (Hijazi et al 2009). Even prior to the use of BIM, Russell and John (1993) analysed case studies which proved savings in time of over 10% and in project cost of over 7% could be realised using constructability practices. These benefits can be to designers, contractors, owners and end users alike. All too often, owners do not get the product they wanted. This is often because they or their designers have interpreted the requirements and the designs differently. Again, Hijazi et al (2009) noted the potential of BIM when fully utilised with 4D scheduling, as a means of testing different design and sequencing alternatives. Differing professions rated the importance of certain benefits differently but all agreed that the use of constructability reviews could help in cost, quality, safety and time among other potential benefits.
The method of procuring projects can be a distinct driver in whether constructability reviews ever take place. In Ireland, the likelihood of a stringent constructability review taking place for a traditionally procured public project are very slim. This is for several reasons, such as having no contractor input during design, limited collaboration between the different professions and a lack of experience in using collaborative tools such as BIM. Regardless of this, the current climate in Ireland does not offer designers sufficient incentives or time to design buildings fully, despite to original intention of the GCCC forms of contracts requiring construction projects to be designed right down to the paint colours. The GCCC form of contract is conflictual in nature and does not lend itself to any form of collaboration between parties. The irony being, that the easiest way to reduce conflict and to ensure the completeness of the design process would be to carry out constructability reviews using all stake holders.
Some design and build projects under the public purse in Ireland do benefit from the use of constructability reviews, however, these do not generally include the end users or owners but are done by the contractor and design team to maximise profit but not necessarily produce a better product for the client. This lack of input by the client is a glaring omission from the process.
In Ireland there is no specific requirement for constructability reviews and thus they are often completed on an ad hoc basis. In Hong Kong, Singapore and Malaysia, systems for scoring buildability have been developed. Buildable Design Appraisal System (BDAS) was introduced by the Singapore Government and Buildable Multi-Attribute System (BMAS) by the Malaysian Government. Many other models predated and preceded these.
In the case of Sutter Medical Center Castro Valley, there was a full IPD approach to the project due to time constraints and the impending deadline to meet specific legal requirements with regard to earthquake protection. The team entered into a formal IFOA (Integrated Form of Agreement). This form of agreements included a share pain and share gain approach. There were profit sharing incentives for finishing on time and ahead of budget. There was a guaranteed maximum price and it was estimated, Khemlani (2009) that due to this integrated approach and continued constructability reviews, that the project was constructed 30% faster than a traditional approach. The design time for the structure alone was reduced by 7 months from 15 months to just 8 months. There is also little doubt that the 4D modelling can help in operational flows. Large idle machinery or hired structures and resources become very evident when they can be visualised. The safety aspects will be discussed in more depth but can also be mentioned under the efficiency savings possible
through implementing constructability practices.
Olatunji et al (2010), cited the improved accuracy in both the model, the quantities it produces and the live interactive updating of these quantities as changes are made as a means of ensuring greater confidence in the project at large. In addition to this, the greater accuracy leads to fewer assumptions and thus less contingency or float requirements. The mistakes found in the initial review of the Honam High-Speed Rail prior to any construction occurring show the enormous potential of using this process. However, the scale of the projects need to be taken into consideration when deciding to use the BIM process in an Irish context in the current climate. Firstly, due to dramatically decreased fees, many design and professional consultants are struggling to survive at all. They simply do not have the money to spend on new software and considerable training in BIM. At the moment, it is arguable that whilst clients believe they are getting design fees at the best value ever, they are unaware that the deficiency in design due to decrease resources being allocated is in fact probably leading to more expensive types of buildings. The easiest way to design is to over design. In architects cases it may simply be spending less time investigating alternative products and more modern solutions. In engineering terms it may be allowing larger size beams and columns rather than pursuing greater analysis in connection details or composite actions.
There is a considerable irony in the fact that many people cannot afford the cost of up skilling and investment in technology due to limited financial resources within the country and sector given that this investment could help dramatically reduce costs to all parties.
At with visualisation being a benefit to the teaching of construction courses, so too is the ability to give students, who otherwise may have little experience or knowledge of construction, a building model in 4D. It allows students see much of the sequencing and methodology of construction and project management. It also affords the students the ability to actually construct a project and work through the sequencings following the logic with class tutors and those with greater experience. It has the potential to change dramatically the way construction is taught and could result in far more knowledgeable construction managers coming out from future courses. It has long since been a complaint of the industry that students who leave college simply do not have a realistic understanding of the problems they will encounter and how to deal with them. This is strongly argued by Thomas and Mengel (2008) as well as Peterson et al (2011).
Finally, in its most simplistic form, as alluded to by Deutsch (2012), 4D models and schedules help people understand how things are put together. They help designers understand the consequences of many of their choices. This is perhaps one of the most valuable benefits of 4D. It removes much of the previous disconnect between designers and contractors. We are all aware of comments when some very difficult detail to construct arrives on plan. In general these comments are about the lack of time designers have spent at the cold face of construction. In such a fast paced specialised construction industry, it is very hard for all professions build up on site experience. This is why 4D models can help all parties understand each other.
As noted in the introduction, many of the headings discussed overlap. This is in fact a symptom of the collaborative and integrated nature of the BIM process. This collaboration ensures that there is a constant intermingling of information through process. Many commentators are at pains to point out that BIM is not simply technology but a process that requires the use of available 3, 4, 5D etc technology and the collaboration of users, constructors, designers owners and end users to extract the most benefits from IT. Items such as visualisation and particularly constructability require a collaborative approach to be useful.
Basu (2007) understood the requirement for early stakeholder involvement in the process. Some of the greatest drivers of the collaboration and integrated agenda were in the US. The General Services Administration (GSA), an independent US government agency tasked with supplying office space to the federal government mandated the use of BIM and 4D scheduling by 2007, acknowledging the potential of BIM. Another major driver of BIM was the Construction Users Roundtable (CURT). This organisations members includes virtually all the multinational which are present in Ireland today, such as Abbot, Baxter, Intel, Johnson & Johnson, Eli Lilly etc.
Intel in Ireland have started using BIM extensively in the planning of its latest expansion. Full design of these plants are not fully complete when construction begins so they are dynamic environments which are in constant design development. It is certain that this project could not be delivered successfully without this collaborative and technological approach.
BIM works particularly well as an aid to the integrated project delivery (IPD) approach. This approach requires the use of collaborative agreements which can help “harness the power of BIM and Lean Construction Methods” Salmon (2008). He believes corporations who use these processes can leapfrog many of their competitors through efficiency savings.
We are well aware that Partnering or Alliancing are not new concepts. These are not agreements which can suit everybody. Procurement rules in Ireland and the EU make them very hard to enter into on public contracts. There is currently no contract available to the government which they could use. In fact, the current GCCC forms of contract specifically attempt to remove all risk from the client and place it on the contractor’s door. This adversarial contract has lead to many arbitrations and litigations and indeed several contractors have failed to finish many of these contracts due to financial difficulties. It is currently very hard to see how the Irish state could harness the potential benefits of this collaborative approach given their intent on using what are widely acknowledged as the most unfair contracts in Europe or the developed world.
Below is a table produced by Salmon (2008) showing the differences between the collaborative and the combative mindsets?
| Collaborative Agreements Traditional Contracts|
Promote Flexibility Promote Rules
Target Cost Estimate GMP/Fixed Price
Target Cost Adjustments Change Orders
Waive Liability Claims Shift Liability Claims
Serves as a Constitution A Draconian Code
Guides Behaviour Dictates Behaviour
Reward Collaboration Punishes Collaboration
The idea with the collaborative approach is to eliminate all non-value adding work (Tulke, Nour and Beucke 2008). This requires that “scheduling runs concurrently with other key processes like architectural design, cost estimating etc” One of the major problems with the construction industry is its inherent fragmentation. Disciplines and professions have always worked apart. Architectural firms, Mechanical and electrical consultants, fire consultants, acoustic engineers, structural engineers etc are often different practices and even when they are under the one practice name, they are often run as separate entities. This has lead to constant duplication due to under sharing of drawings and models.
The advent of BIM as the current trend has forced disciples to look differently with regard to its implementation. Particularly if it is being driven by people who will become potential future clients of all the suppliers of these services. Additionally, having used the process, many designers understand the benefits in reducing their own time on the process. They are not being asked to redesign at a later stage because these issues have been discussed and solved collaboratively, have become evident through the shared model and clash detections.
True collaborative approaches require incentivisation to ensure the team have reason to work together. This is normally dealt with through a sharing of gain as well as a sharing of the pain. The idea is that savings made for the client either in the short or long term will be partially shared out with the other stakeholders. Conversely, mistakes made later on in the process can also lead to deductions in profit. However, the use of full BIM with IPD is likely to be a slow process to become widespread throughout the industry. There are many issues such as education, trust and legal issues which will first need to be addressed.
Increasingly, 5D models are being produced which include links with the 3D model, the 4D schedule and the 5D cost and quantity estimates. The quantity surveying practices are also key to full collaboration. With the use of the quantities taken off and a list of their locations, the construction manager can advise and decide on productivity rates and thus make educated assessments on the durations of activities.
Koo and Fischer (2000) concluded in a feasibility study carried out on commercial construction projects, that 4D scheduling helped accelerate understanding of construction works. The sharing of data centrally is also one of the effects of a collaborative approach. Generally the master model is held remotely while different professions and disciplines feed into the model. This helps the model remain a live document and reduces the need for duplicating of works. The sharing of data has its own legal issues in relation to ownership of components, copyright and commercial secrecy or sensitivity. However, there are good examples available on how to overcome these issues and how successful these collaborative processes can be. As previously discussed, Sutter Health project in Castro Valley completed a $320 million project having entered into a collaborative agreement with its designers and contractors as did the University of Washington in relation to Benjamin D. Hall. There are of course many other success stories along with stories which have ended in the courts.
Safety is perhaps an area under explored in relation to advancements in construction technologies. BIM and 4D scheduling have shown very exciting potential and advancements in this area. Limited amounts of work were done in this area in the early part of the last decade and before. However, once again, with the advancement of technology, many integrated technological and construction management practices that can help reduce injury and deaths have emerged. At a very basic level, the use of BIM has dramatically increased accuracy and confidence in project documents such as design drawings and models. This in turn has lead to an increased ability to prefabricate many components previously constructed on site. Most prefabrication plants have much better safety records than dynamic construction sites. They use far more automated machinery and systems in a much easier to control environment. This reduces the time spent on site and the resources required on site.
Regardless of the complexity of the projects constructed, it is likely there will need to be temporary structures formed during construction. These could be temporary roads to gain access around the building, scaffolding to construct blockwork or install windows, canteens and offices to service the site population, security camera poles, fencing, access platforms, cranes, structures to support components in temporary states. Etc. The list can seem almost endless. All these items take up space on a site and depending on the method of construction and the equipment employed; they can dramatically reduce the spaces one has to work in on sites. They can also easily restrict access to important areas of work. For example, if scaffolding was placed between an existing building and a proposed new building, it could restrict any access between the two buildings, if pipework or services were to be laid, the scaffolding might need to be removed. 4D scheduling allows someone to physically see these problems scheduled in durations. Pipework beside scaffolding could have subsidence issues and slippage. Benjaoran and Bhokha (2009) noted its ability to analyse congestion and accessibility to working space more effectively than standard Gantt charts. This is because Gantt chart has representations of time and activities in text and bars. The do not represent time and space.
Of course, these visual representation tools are helpful but there are far more powerful tools which can help safety standards improve. Particularly in relation to the structural stability of permanent structures whilst in a temporary state during construction. The structure is dynamic and thus constantly changing. A very simple example is that of building a single steel column on its own in a sky scrapper to the top. We know that without lateral support of further beams and columns, it will fall over, buckle or pull from the foundations. Insitu concrete is in need of even more analysis as it begins as a liquid and takes 28 days to reach its final characteristic design strength. Until it reaches this required strength, it cannot be used for the purpose it is designed for, however, during construction; it will be put under entirely different structural criteria. All these constantly changing dynamic loads require temporary treatments and supports. However, without 4D schedules, the model, unlike a building remains in static state. By linking time to these structural components, it is possible to carry out time related structural analysis using the actual structural model in BIM. If this is carried out at design stage, it may determine the preferred material and the construction methodology in order to save time and money. Hu and Zhang (2011) developed a system which addressed 3 elements of safety in 4D. 1) 4D structural safety analysis. 2) 4D construction conflict management analysis. 3) 4D layout collision analysis and management. This wide ranging dynamic tool could improve safety dramatically within the construction industry.
On the Homan High Speed Railway, they also carried out safety analysis by running a model showing equipment in virtual operation first. This helped eliminate congestion and accessibility issues on site. Equipment can be shown arriving and leaving site at anytime. Additionally, a safety avatar was added to the updated progress model and could visit the site remotely. The main benefit of the avatar is to help train others. Data is embedded in the model showing current codes of practice and risk assessments.
This training element extends to formal education in construction management courses such as those in the Managing Fabrication and construction class in Stanford University and Integrated Project Management class in Twente University. Students and newly qualified graduates cannot hope to understand the construction industry without experience or at the very least without having had realistic or actual problems presented in a medium such as BIM. It allows them a greater understanding of the direct consequences of sequencing in 4D. “While mistakes in the classroom result in lower marks, mistakes in the field can affect morale, waste resources, and in the worst-case scenario cost someone's life.” (Peterson et al. 2011).
It has long since been acknowledged that the removing of human decision making in certain circumstances will obviously result in the removal of human error. This has been done in construction in many forms such as the advent of structural analysis tools and packages, better testing equipments and regimes among many other advancements. These technological advancements can also remove some safety uncertainty in construction. Zhang et al (2012) used BIM to include algorithms which can create rule based checking systems for safety. Initially this was concentrated generally on falls from height as they represent the greatest cause of fatalities in the USA which is also true in the Irish construction industry. This rule based system was integrated into the 4D schedule also. As openings in floors or leading edges appear during construction, the rule based system would determine the treatment required for these. The algorithms would be written based on current legislative requirements and best practice. For example, if the drop was less than 300mm it might suggest simple signage and warning tape. If the fall drop was greater it would suggest handrails 1.1m high. If and opening was less than 500mm x 500mm it might suggest covering it or if less than 50mm doing nothing at all. This system can remove the danger of humans simply forgetting legislation or not getting to the problem. It can direct general labour to keep up with the safety requirements without first having to get direction from safety officers. All too often, accidents occurred because a simple solution had not been prescribed due to management not having gotten to the problem in time.
| Clash Detection|
Clash detection has long since been the buzz word in BIM. This is because it is possible to put a value on the savings made from eliminating problems found during a clash detection review. According to the report by the contractor “use of the 3D digital model, prevented 1200 collision of steel elements and sped up steel erection”. On the Benjamin D. Hall, Washington University, they estimated 1500 potential clashes were eliminated. While CURT indicated clash detection was one of the most promising aspects of BIM, particularly in pharmaceutical and manufacturing plants with heavy mechanical and electrical elements.
The Homan High speed railway project found clash detection invaluable. Whilst the Birds Nest (National Stadium Beijing 2008 Olympics) assessed over 2400 nodes. As a teaching tool it has proved invaluable in allowing students see where mistakes are being made without having to spend wasteful time trawling through countless 2D drawings instead of productively learning. Clash detection can be broken into three categories or three types of clashes. 1) Hard clash. 2) Soft Clash/Clearance Clash. 3) 4D/Workflow Clash.
A hard clash is simply when two objects occupy the same space. For example, a pipe cannot go through a wall without there first being and opening. Rule based algorithms can be used to allow automatic solutions too many hard clashes. Clash detections can be run against sub-sets of the model. One could run mechanical ducting against just ceilings or just electrical sets or walls against steel structure etc.
Soft clashes refer to allowable tolerances or space. Buffer zones between components. These spatial allowances may be to provide space for ongoing maintenance, future expansion, safety codes or expansion and contraction among other reasons
4D/Workflow clashes refer clashes in scheduling work crews, equipment/material fabrication delivery clashes and other timeline issues.
BIM has the ability to produce full and accurate quantities for any components built in the 3D model. Each component is made up of a specific ingredient. This intelligent model allows a clear breakdown of very specific quantities to be produced. (Tulke, Nour and Beucke 2008) indicated that 4D software at the time could not handle much of this data. They were simply a basic link to the component but could not use quantity, cost or geometric data etc. Also, software was very expensive at the time.
However, even accurate quantities gave considerable help in producing budgets and time estimates based on productivity rates. If the model changed, so to would the quantities. This eliminated the need for time consuming remeasure. Unfortunately, a change in the model did not create an automatic link to change the measures in the chosen quantity surveying software or the scheduling software. These still had to be extracted from the 3D software and inputted manually. The confidence in the quantities allowed far more certainty in budget estimates and less concern about the requirement of adding contingency. It also allowed for far more confidence in procurement.
“ The spirit of BIM is collaborative and integrated by definition and goes unrealised when a design team creates a BIM without planning, scheduling and cost professionals contributing to the model in 4D and 5D”(McCuen 2008). How far one goes with BIM is often down to the maturity level of the team and its respective parts. To use fully integrated 3D, 4D and 5D are still very uncommon. This is down to software costs and educational restrictions. This applies to the US as well as the UK and Ireland. The certainty of quantities allow several different models to be assessed for the most cost effective solutions prior to construction.
Change in the construction industry has always been slow due to its conservative nature. Olatunji et al (2010) also identified the potential conflict of interest professionals might have with the use of BIM. This is particularly evident when it comes to the quantity surveying practice. Using accurate 3D BIM models produced by architects, engineers etc, means that a schedule of quantities can be produced at the push of a button. Previously a quantity surveyor could spend very long periods of time physically measuring and taking of quantities from 2D drawings. The construction industry has not historically embraced IT or technological advancements nearly as quickly as most other sectors in the economy. In Ireland we have long since listened to the mantra of how productive our construction industry is, but this is only in relation or comparison to construction sectors in other jurisdictions. In fact, construction productivity declined since the 1960’s in the US and most other developed countries whilst other sectors showed dramatic growth in productivity. Many analysts place these results squarely at the construction industries lack of integration, inability to embrace IT advancements, low off site fabrication, fragmentation on professional services and protectionist stances from vested interests. Quantity surveyors are aware that BIM could reduce their workload significantly. However, they need to emphasis and concentrate on the other services they provide. They are not simply a profession that does basic take off measurements but rather give other services such as contractual advice, financial advice, budgeting and project management among other areas of expertise.
Despite BIM’s accurate quantity measurement ability, there remains the issue of differing standard methods of measurement. In Ireland we generally use a version of ARM (Agreed Rules of Measurement) whilst in the UK they use SSM (standard Rules of Measurement) or for civil works they use CESSM. In the US and Australia they use other methods of measurement. As noted by Olatunji et al (2010), it is likely that software companies will only develop measurement software to suit the extraction of BIM quantities in the method of measurements in the largest markets. This would almost certainly not include Ireland which has ARM as its own isolated method. It would therefore be advisable for the construction industry to liaise with their international counterparts to produce a common means of measurement which will allow us utilise the BIM software’s.
Finally, as already discussed, taking off quantities is generally a long, tedious and laboursome process. Whilst it is an analytical and methodical task, it does not require highly intellectual skills. During education, it is a process which requires long periods of time when this may be better served on more complex value adding training and education.
| Progress Tracking
In most cases, 4D scheduling using BIM is simply the linking of activities in a Gantt chart to a specific BIM component. For example, you could select all the columns on the ground floor of a project in the 3D model and link them to a task called “construct ground floor columns”. These would be highlighted as under construction for the duration that has been assigned to the Gantt chart bar. In general, these schedules are first done in specific scheduling software such as ms project, asta powerproject, primevara or the like and simply imported into a software package like Vico, synchro or navisworks which allows the link be made between the model and schedule. However, it is now
also possible to set rates of production and cost against the quantities produced from the BIM model. Thus when a quantity changes in the model, so too does the duration and the value of works. Whilst this software is still not widely used and tested, it has the potential to dramatically reduce the time spent on estimating and rescheduling. It will, like many standard software packages, also allow Earned value analysis be carried out.
However, previously progress tracking and earned value analysis was a manual task which was difficult to do accurately in the construction industry. It required someone to do an assessment of the percentage work complete on each activity. Without physically measuring each task, it was impossible to do this accurately and even if estimating roughly the progress of each task, it still required someone to visit site and make this assessment of each of these tasks. On a large site, this would take a considerable length of time and potentially not be accurate enough to flag poor performances in schedule or budget. Thankfully, although not widely available yet, much work has been done in automating progress tracking. Turkan et al (2012) carried out studies on integrating many current technologies. They carried out the tests on the technology in the Engineering V building in the University of Waterloo which showed that automated tracking met or exceeded the current methods for accuracy. There are currently several technologies which can help in carrying
out automated tracking; these include LADAR (laser detection and ranging), GPS, Ultra wide band tags and photogrammetry. Many sensing technologies do not naturally produce project oriented data. However, with the correct mix of technologies it is possible to create 3d data stored as dense cloud points. This makes it possible to scan rooms, and update the 3D and 4D models. Laser scanning also offers the ability to quickly validate construction work carried out in relation to what was expected or designed. This can obviously greatly increase quality as this validation will force contractors to ensure the construction is carried out as per the drawings as it will be noted in progress reports.
It has also become apparent that the critical path method of scheduling is becoming less utilised in relation to 4D scheduling. Whilst most BIM oriented 4D scheduling packages still offer CPM Gantt style software, most now also include the location based scheduling software Line of balance/Flowline scheduling method. The argument has been that CPM focuses too much on the duration of the project and does not take into consideration enough the flow of resources. Location based scheduling (LBS) is a combination of CPM and linear scheduling methods. This method is perhaps becoming more prevalent in other countries rather than Ireland due to the high rise construction which takes place in them. Location based scheduling is particularly useful for repetitive tasks in different locations. Like floor levels.
| Project Delivery & Alignment|
In construction, project alignment has long since been discussed. There has been a general acceptance for years that the traditional process is far to conflictual and that the potential for any of the party members achieving exactly what they each wanted is almost impossible. This is because they do not have shared goals. In fact they tend to have very differing objectives. Alignment is the process by which team or project stakeholders are brought together to achieve common objectives.
In the instance of construction, the objective should be to provide a building owner or client a building which satisfies their requirements at the lowest cost, over the shortest timescale and to the highest standard of quality. The traditional approach has been to create contracts which force each of the project team to comply with the requirements of their roles. Alignment or alliancing tries to get project teams to buy into the common objectives.
| In construction a form of alignment process is IPD or integrated project delivery. The AIA (American Institute of Architects define IPD as “a project delivery approach that integrates people, systems, business structures and practices into a process that collaboratively harnesses the talents and insights of all participants to optimize project results, increase value to the owner, reduce waste and maximize efficiency through all phases of design, fabrication and construction.” |
Construction projects have been historically plagued with low productivity, poor communications, lack of common goals between teams, poor distribution of risk and general mistrust. In fact, since the 1960’s, construction was one of the few industries which actually saw decreases in productivity for several decades. Productivity dropped because of delays due to conflict of changes or variations, poor initial design prior to starting, buildability issues due to lack of contractor involvement in design and poor risk or reward systems. Risk and uncertainty on project is directly attributable to the collaboration of all expert professionals. “Owners are intensely frustrated by the waste generated in the delivery process due to both the lack of coordinated and complete information as well as by poor alignment between practitioners” Henry C. (Peter) Beck III
This is why the IPD or alignment approach is so attractive to the construction industry. The greater the initial involvement of the major project experts prior to construction stage, the lower the risk. We are all aware that the better we plan a process and research it, the better the outcome. Traditionally, architects did plan, elevation etc drawings, the structural engineers took the drawings and created a structural model and finally the M&E consultants added to this. However, the collaboration even between the professionals was poor. Inevitably, beams clashed with pipes which had insufficient space to fit in the ceiling voids or a myriad of other problems arose. This lead to change/ Variation orders and disputes between all parties. The IPD process asks all parties to share in both the risks and the rewards.
Architects themselves do not receive sufficient remuneration to co-ordinate the process nor do they have sufficient knowledge to do so. They would embrace the opportunity to learn more about the buildability and indeed cost of some of their proposals at an early stage. Foreman and site managers also suffer greatly from a lack of detailed specification at construction stage and simply cannot build accurately without it.
This solution can be used with relative ease if required in the private sector. It is much harder in the public sector. The appointment of a contractor cannot be on price as there is no means of pricing a building which has not been designed. Contractor selection is an integral part of the process. Given the levels of transparency and accountability required within the public sector, it is a minefield as how to draft a fair piece of selection guidelines. Also, following the contracting authorities initial lack of success in implementing the EU Directives legal ethos of “transparency, proportionality, fairness, equal treatment and non-discrimination” it seems unlikely they would do a better job of this difficult proposition. When turnover criteria are sometimes required to be 5 times the actual project size, it is no wonder why even the largest firms of contractors or architects in Ireland are unable to tender for certain works within their own jurisdictions despite the fact they would be more than capable of carrying out the works. This off course applies to the smaller contractors too, they spent 20 years prior to the advent of such ludicrous criteria proving and showing they were capable of carrying out such works, only to be told the paperwork suggested they couldn’t. It is clear that IPD or Alignment has considerable benefits to give to the construction industry but it is also clear that there will be considerable conflictual issues to arise at tender stage if it does succeed.
Finally, the improvements in technology have also made the use of IPD an even more certain prospect. Web based collaboration tools such as Google docs or dropbox have made data sharing far easier. Web based SaaS (software as a service) has also allowed much greater governance of projects and sharing of data globally. There are many SaaS based construction management software platform which can help the process. However, BIM or Building Information Modelling is perhaps the most exciting and useful integration or alignment tool available. It requires full and early team involvement and collaboration but the results are worth this. The design is done in 3d modelling and a master model is created. M&E engineers, structural engineers etc add their information to the model. The contractor can take off accurate quantities and can visualise the project adding to the ability to flag buildability issues at the earliest stages. They can also schedule the project in 3d. Visually showing how the building will be built. It is also possible to run clash detection analysis. This shows any clashes between services or structures which can be eliminated prior to going on site.
| Conclusions & Recommendations|
The above paper has shown the relative non-existence of any true BIM process in Ireland. The lack of existing or current BIM practitioners and knowledge of BIM in the Irish construction industry has pointed toward the need for significant further research to take place. The lack of any concrete information on BIM an Irish context also leads toward the same conclusion. This paper is a significant first exploratory stage in the research process. It has identified many areas which, with further research could prove hugely transformative to the Irish construction Industry. Chief among these being the implementation or feasibility of changing our traditional procurement process and or project delivery methods.
There is without doubt, over the coming years, when BIM has been used even in a fragmented manner, a large volume of research which could be carried out into integrated project delivery using BIM. The use of BIM in conjunction with lean construction methods can also be further explored. As BIM is only in its infancy, the evidence based research is not fully possible yet. Experience and outcomes are simply not available. The further stages of research will need to be done in significantly frequent intervals as BIM maturity levels increase and BIM permeates the Irish market. The industry needs to move away from the current fragmented project delivery method which has been proved to be so inefficient and risky in the past. The number of contractors going into liquidation is frightening.
It is clear that BIM and 4D scheduling has dramatic potential benefits to all stakeholders involved in the construction industry. If it is to become a reality and used widely in Ireland, it must be driven by the client or owner of the project and there must be a buy in to the process from all.
Its implementation is not without its considerable challenges. Primarily this is the initial investment required during the worst recession the building industry in Ireland has ever experienced. Hardware, software and education costs will make this slow. Many of the private foreign direct investment multinationals are starting to expect this process to be available to them. However, without Governmental support, BIM is unlikely to become the norm in the near future. BIM is a process which requires collaboration. Unfortunately, current government contracts are adversarial and thus BIM cannot be a worthwhile process under those circumstances.
This does not mean that private construction clients should not drive its implementation. I would, however, suggest that it be done in a phased manner. This would allow SME’s an opportunity to invest over a longer period. There is always the danger that only those currently able to afford the investment will be able to tender for work should its requirement become mandatory on many projects in too short a timescale.
There is also a danger that larger supplier’s products will be specified by designers simply because they have a BIM database of these products and not because they are the most cost effective or relevant to the project. This could lead to poor value for money.
Currently, it is hard to justify the use of full BIM on smaller scale projects. This is not because BIM is not more efficient, it is because the level of analysis required on smaller projects is often not as great. This would not mean that much of the BIM process could not be utilised. The level of expertise to use full BIM would require a certain physical number of people who were able to carry out the different tasks. In some instances, the physical numbers allocated to smaller projects would make this impossible. Particularly for smaller contractor or designers who do not have infinite numbers of experts.
BIM as a construction management training and education tool is a very positive advancement. Colleges and Universities should consider using it to give their students virtual problems which can help their understanding and give them some of the experiences they can currently only learn onsite.
Some of the technologies can also help decrease the time spent doing time consuming low intellectual works, freeing up time for more complex areas of learning or work. This applies to both work and education.
It is also imperative that the surveying professions and their representative bodies investigate on how best to facilitate the use of BIM as a means of taking of quantities. This may mean producing a new standard method of measurement which will allow Irish companies use the most up to date software available from around the world.
Both contractors and designers alike should further investigate the use of BIM as a safety tool. In collaboration they could utilise the analysis of dynamic structures. Contractors could use rule based systems to ensure safety systems are in place at the right time and in relation to the progress of a project.
The Irish construction industry at large should consider following the lead of many other countries in drafting a constructability assessment protocol. This is not exclusive to BIM use but as general good practice.
Automated progress tracking can also help increase quality in the industry but also be used as an early warning system for poor progress and poor quality. Whilst clash detection can be used to eliminate design mistakes prior to construction and save considerable money from change orders, automated progress tracking can highlight mistakes on an ongoing basis during construction. The earlier a mistake is found the earlier it can be rectified and stopped from occurring again.
It is important to note that there are considerable challenges to the easy implementation of BIM. With collaboration of design and construction, so too comes the collaborative nature of design responsibility. Legally, there are many unanswered questions.
Finally, future research should look at BIM form a facilities management perspective. This will allow virtual safety and operations and maintenance manuals. Simply by clicking on an item of plant, equipment, furniture in the 3D model, embedded data could show where it was purchased, data sheets about it, when when it was lasts serviced etc. Also, if a building is facility was to be extended, so to could the model.
Akinci, B., Fischer, M. and Kunz, J. (2002), “Automated generation of work spaces required by construction activities”, Journal of Construction Engineering and Management, Vol. 128No. 4, pp. 306-15.
Allen, S.G, 1985, WHY CONSTRUCTION INDUSTRY PRODUCTIVITY IS DECLINING, NBER WORKING PAPER SERIES
Basu, A (2007) “4D scheduling – a case study”, AACE International Transactions, PS. 12#
Benjaoran, V., Bhokha, S. (2009) “Enhancing visualisation of 4D CAD model compared to conventional method” Engineering, Construction and Architectural Management, Vol 16, 392 - 408
Beukers et al, 2006, The Procurement Alignment Framework, Construction and Application, WI – Schwerpunktaufsatz
Carbasho,T, 2008, Integrated Project Delivery Improves Efficiency, Streamlines Construction, Lean Management Approach Eliminates Waste and Enhances Project Outcome,
Cho, H., Lee, K. H., Lee, S. H., Lee, T., Cho, H. J., Kim, S. H., Nam, S. H. (2011) “Introduction of construction management integrated system using BIM in Homan high-speed railway lot no. 4-2, Report. Civil Engineering Technology Department, Ssangyong E and C, Seoul, Korea.
Construction Industry Institute (CII). Constructability: A Primer. Austin, TX: CII, University of Texas, 1986.
Construction Industry Research and Information Association (CIRIA). Buildability : An Assessment. London: CIRIA, 1983.
Deutsch, R. (2012) “BIM beyond Boundaries” http://www.di.net/articles/bim_beyond_boundaries/ [Accessed 18 February 2012]
Frausto-Robledo, A, 2008, AIA: American Institute of Architects delivers new contract documents to encourage Integrated Project Delivery
Henry C. (Peter) Beck III -Beyond IPD: The Integrated Enterprise Challengehttp:// www.aia.org/practicing/groups/kc/AIAB081060
Hijazi, W., Alkass, S., and Zayed, T. (2009) “Constructability Assessment Using BIM/4D CAD Simulation Model”. AACE International Transactions, BIM.04.1 Hu, Z., Zhang, J. (2011) “BIM- and 4D-based integrated solution of analysis and management for conflicts and structural safety problems during construction: 1. Principles and methodologies”. Automation in Construction, 20(2), PP 155-166
Hu, Z., Zhang, J. (2011) “BIM- and 4D-based integrated solution of analysis and management for conflicts and structural safety problems during construction: 2. Development and site trials”. Automation in Construction, 20(2), PP 167-180
Jensen et al,2006,Project Relationships – A Model for Analysing Interactional Uncertainty, International Journal of Project Management, Elsevier
Jongeling, R. and Olofsson, T. (2007), “A method for planning of work-flow by combined use of location-based scheduling and 4D CAD”, Automation in Construction, Vol. 16 No. 2, pp. 189-98.
Khemlani, L. (2009) “Sutter medical center Castro Valley: Case study of an IPD project”. Building the Future - AECbytes http://www.aecbytes.com/buildingthefuture/2009/Sutter_IPDCaseStudy.html [Accessed 15 January, 2012]
Koo, B. and Fischer, M. (2000) “Feasibility study of 4D CAD in commercial construction”. Journal of Construction Engineering and Management, Vol. 15 No.2 pp 189-98
Ma, Z., Shen, Q. and Zhang, J. (2005), “Application of 4D for dynamic site layout and management of construction projects”, Automation in Construction, Vol. 14 No. 3, pp. 369-81.
McCuen, T. L., (2008) “Scheduling, estimating and BIM: a profitable combination". AACE International Transactions, pp BIM11-19.
National Building Information Model Standard Project Committee, http://www.buildingsmartalliance.org/index.php/nbims/faq/ [Accessed 18 February 2012]
Olatunji, O. A., Sher, W. and Gu, N. (2010) “ Building information modelling and quantity surveying practice” Emirates Journal for Engineering Research, 15(1), 67-70
Peterson F., T. Hartmann, R. Fruchter, and M. Fischer (2011). “Teaching Construction Project Management with BIM Support: Experience and Lessons Learned”. Automation in Construction 20(2): 115.
Rischmoller, L., Alarcon, L. F., and Koskela, L. (2006) “Improving value generation in design process of industrial projects using CAVT.” Journal of Management Engineering, 22(2). 52-26
Russell, J.S. and John, G. G. (1993) “Comparison of Two Corporate Constructability Programs” Journal of Construction .Engineering Management. 119, (4) 769-84.
Sacks, R., Koskela, L., Dave, B. A., and Owen, R. (2009) “The interaction of lean building information modelling in construction” Journal of Construction Engineering and Management
Thomas, J., Mengel, T. (2008) “Preparing project managers to deal with complexity-advanced project management education, Excellence in teaching & learning for project management” International Journal of Project Management, 0263-7863
Tulke, J., Nour, N., Beucke, K. (2008) “A Dynamic Framework for Construction Scheduling based on BIM using IFC” 17th Congress Report IABSE
Turkan, Y., Bosche, F., Haas, C.T., and Haas, R. (2012) “Automated progress tracking using 4D schedule and 3D sensing technologies” Automation in Construction, Vol. 22, pp. 414-421
Turner, J.R, Muller, R., 2004, Communication and Co-operation on Projects Between the Project Owner As principal and Project Manager as Agent, European Management Journal, Elseviar
Turner, J.R, Simister, S.J, 2001, Project Contract Management Theory of Organisation, International Journal of Project Management, Elsevier
Wickersham, J. (2009) “legal and business implications of building information modelling (BIM) and integrated project delivery (IPD)”. Rocket: BIM-IPD legal and Business Issues
http://isites.harvard.edu/fs/docs/icb.topic552698.files/Wickersham%20BIMIPD% 20legal%20and%20business%20isssues.pdf [accessed 14 January 2012]
Zhang, S., Teizer, J., Lee, J.K., Eastman, C.M., Venugopal, M., (2012) “Building information modelling (BIM) and safety automatic checking of construction models and schedule” Automation in Construction