Client Mandated BIM Requirements for Tender and Construction
The Midfield Terminal Building of the Abu Dhabi Airport (MTB-ADIA) is a $3billion, 700,000-sqm development, providing a terminal building with passenger and cargo facilities, duty-free shops and restaurants for a total capacity of 27-40 million people per year. The unique X-shaped building will be located between the two existing runways, giving the name ‘Midfield’.
Designed to render an open and spacious environment the MTB features large column-free zones with inclined steel arches supporting the soaring roof. A large hall leads passengers to the centre of the building, which contains a hotel, lounges, cultural outlets, stores and a park-like garden.
Guided by environmental objectives the MTB is designed to meet the UAE’s Two Pearl Rating for Sustainable Design. Towards this goal the terminal limits the use of potable water by incorporating dry climate landscaping and uses low energy lighting supplemented by daylight filtered through the transparent walls.
The project is challenging in terms of engineering, construction and procurement due to the unique nature of the design and the inherent complexities of its operation. Anticipating the challenges that such complexities posed the owner, Abu Dhabi Airport Companies (ADAC), sought to promote technologies that would facilitate the delivery of the project and enhance its operation throughout its lifecycle. One such initiative was the requirement for BIM-integrated processes. This was enforced by a set of demanding, ambitious and quite unique specifications.
BIM Specifications at Tender Phase
Project tender requirements stipulated that the General Contractor must develop, communicate and share a comprehensive BIM for all disciplines, involving all Sub-contractors’ and manufacturers’ scope. The BIM Implementation, therefore, had to cover Engineering and Design (clash mitigation, design coordination, RFI system, shop drawings), Project Controls and Planning (Scheduling, Cost Estimation, Progress, and 4D studies), Contractual and Quantity Surveying (Quantity take-off and measurements) and Manufacturing (Digital Fabrication). Site logistics, temporary installation, scaffolding, and formwork were also to be BIM driven.
Temporary Works Constructability and Optimization
The client invited five major international Joint Venture (JV) Consortia to bid for the construction contract of the MTC project. The JV of CCC, Arabtec and TAV developed an approach based largely on the experience and expertise developed in-house by CCC over the past decades. CCC’s accomplishments in this field are recognized by its peers and reputed manufacturers of BIM Software. Their BIM processes were developed entirely in-house, building on the needs of its core business and the control systems that had been established within the company.
A Bold Approach
The complexity of the Midfield Terminal Building project posed many challenges to the General Contractor prior to and during construction. Mitigating these challenges, ensuring the quality of the finished product and meeting the stringent demands of “BIM-driven” project delivery, demanded an enormous commitment from the JV in terms of pre-planning, technical understanding of the project and available resources. Indeed it was felt that the only way to meet these demands and be prepared for project award was to commence the BIM process prior to the project commencement.
A bold initiative was taken by CCC and its IT/BIM department to start developing the 3D BIM platform for the project eight months before the project was even awarded. This approach enabled the JV to get a head-start on the project (in the event that they were successful in their tender), however, it also ran at great risk and cost in the event that the tender was unsuccessful.
An initial BIM was developed from the tender documents at CCC’s BIM centres. A decision was also made to commit to the training and preparation of forty additional BIM engineers in the event of a successful award.
Construction Sequence – 4D Studies
The position of ‘BIM Engineer’ requires professionals with multiple skills. Consequently CCC assembled top quality engineers at a range of levels – senior, experienced and young engineers – through a rigorous selection procedure. Intensive and ambitious training was provided to the new recruits to orient them on the BIM workflows, authoring, project controls, design coordination processes and many other concepts that are needed for an effective and fruitful BIM implementation.
The training, which lasted for more than a year, included the extensive use of the software for creating and modifying geometry in 3D, introductions to all design and project control concepts and participation in real, medium to large scale projects. This allowed the team to develop essential skills and knowledge base in real project conditions.
Drawing Traceability and File Management
During the last eight months of the training the new recruits were deployed under the supervision of more experienced BIM staff to develop the initial model (LOD 300). This model was then used to integrate with the initial WBS (Work Breakdown Structures), capture the project scope, extract material take-off reports and link them to the project Bill of Materials and finally compare it to the tender BOQ.
The tender BIM would enable the JV to start the project – if successful in their tender – with a wealth of information, ready RFI’s (Request For Information), design discrepancies, scope management and a good environment for initial logistics and constructability studies.
Clash Detection and Issue Reporting
BIM Journal and The BIM Hub would like to thank Issam El-Absi, Manager IT & Engineering (BIM, GIS & Civil), MTB Project BIM Manager at Consolidated Construction Company (CCC) as the author of this article.
BuildingSMART ME, BIM advisory team developed the BIM Specification for Abu Dhabi International Airport (MTB-ADIA).