BIM poised to take industry forward
BIM is the way forward for the construction industry, says Tahir Sharif, who heads the Tekla ME, the regional office of Tekla Corporation, which aims to revolutionise precast concrete detailing with its innovative software.
01 April 2007
Building Information Modelling (BIM) – a new, collaborative model-based way of working – is the way forward for the building and construction industry, as it provides smooth workflow and efficient information management and enables increased productivity, higher quality and lower costs.
The BIM concept – already validated in mechanical, plant design and steel construction – has been introduced to the precast construction sector by Tekla Corporation through Tekla Structures, which covers the entire building process from conceptual design, planning, project management, detailing, manufacturing and site erection in one advanced fully-comprehensive software solution.
Using BIM software, an entire project can be structurally designed and planned producing a final, integrated building or product model. Here, the design information covering an entire construction project is produced and managed using a single 3D model. As the model’s intelligence keeps all components reliably up to date, current information is available to all stakeholders at all times. Work duplication is minimised and many lower-level tasks are automated, allowing designers to concentrate on the essential.
BIM finally brings to fruition what the building industry expected of CAD in the early 1980s: it helps the entire building process value chain achieve a faster, higher quality and richer design process.
Product modelling
Over the years, it has become increasingly apparent within the building industry that the only solution for truly efficient building information management lies in 3D product modelling. Modelling-based solutions have already been pioneered in niche fields for over a decade, with impressive gains. With the development of telecommunication infrastructure, IT and industry-specific standards, the entire building industry is now reaching the key prerequisites for adopting comprehensive BIM applications.
The modelling-based solutions available on the market today can be divided into two main categories. The ‘bottom-up’ modelling technology – driven particularly by mechanical and plant design – creates parametric models of individual pieces. With this technology, building models are based on tightly integrated but independent models of individual objects. As a result, individual objects and the output generated from them are well managed. However, managing models that include a large number of objects with complex relationships is problematic.
In contrast, ‘top-down’ modelling technology has been created especially for modelling buildings that incorporate thousands of objects. The basic objects are first modelled without details, and the logical relations between building objects are created with connections that also define the objects’ final shapes. When changes occur, the related building objects automatically adapt to the new situation. The ‘top-down’ concept keeps building object libraries compact and makes the management of the entire building extremely easy and effective. The power and benefits delivered by this technology have been proven during a decade of everyday use in the steel construction industry and are now being seen in the precast construction industry.
Integration
The current structure of the building industry is characterised by localisation and segmentation. Processes consist of small islands of automation on which the parties involved work co-dependently but by using their own particular tools. At present, change management is a costly bottleneck due to an inefficient information flow. The adoption of modern modelling technology on one island has an effect on the performance of individual units, but it doesn’t do much to improve the overall situation since the value chain as a whole is unable to exploit the results.
Three possible roads provide the means to move from the current state of affairs into BIM. The most obvious one is the integration of existing tools. The main challenges in this approach are the management of the fragmented information and support for the information roundtrip. All solutions in the industry should speak the same language and use the same terminology – a goal still very far in the future despite huge efforts towards standardisation.
The second alternative is to integrate the entire BIM under the umbrella of a single CAD software package. The use of one CAD platform would facilitate superior interoperability. However, the depth of information would suffer as the capabilities of existing CAD-platform-based solutions are far from the best-of-breed applications available on the market. The effort needed from software vendors to bring CAD-based solutions to the same level is not realistic.
The third option is to create subsets based on best-of-breed solutions and integrate them with standardised interoperability tools. Among the islands of automation, areas such as architecture, plant design, HVAC (heating, ventilation and air-conditioning) and structural design form clearly discernable island groups characterised by intensive, diverse internal information traffic. Communication between such island groups, however, is more standardised and scheduled. Island-group-specific, highly-integrated solutions connected to other BIM subsets and to the outside world via open interfaces make it possible to integrate the whole archipelago and hold onto the best-of-breed benefits.
Advantages
Using the multi-material BIM concept allows engineering practices to visually share building information with other companies and platforms, providing true collaboration. Scheme development and refining can be quickly completed as all the information is always concurrent in one place, allowing the free flow development of building schemes and ideas. Any information can be encapsulated within the object database, which can be refined to suit any project requirement, including information from the client and architect.
BIM can be used upstream and downstream in the contract, so the model can be passed onto the steelwork or concrete contractor and then back to the engineer or client for approval. All the construction drawing information can be stored in one place allowing the full-cycle support, providing a true 3D visual communication tool. Total control and elimination of errors are possible, as all information requirements are automatically produced from the model. It is far easier to interrogate the model than to wade through hundreds of drawings either presented in an electronic format or on paper.
Working on the same intelligent model facilitates efficient change management and information storage for all stakeholders involved in the structural design process. All output – from drawings and technical documentation to fabrication data – can be produced from the same model throughout the process. Revisions are made automatically as changes take place, and conflicts are detected and resolved as they appear. Intelligent change management like this is essential in today’s building process where stages can overlap quite heavily: projects proceed in phases, some of which may still be in the engineering stage while the earlier phases may already be constructed.
The model-based way of operation also significantly benefits various processes parallel to BIM. Using interoperability tools, the same model can easily be made available to closely-related functions such as HVAC or electrical design. Tasks like cost calculation, project management and ERP can also be carried out based on the information stored in the building model. The entire alliance at work on the same project can follow the project’s status in all participating organisations.
In the building industry, pressure is mounting for shorter project run-through times, higher efficiency and better building quality. The current practice of sharing tasks and responsibilities will be swept aside by the more efficient collaboration and project management made possible by BIM. Fundamental changes will take place because collaboration between a team that has learned to play well together is much easier than cooperation between unknown parties. The industry will witness the emergence of larger organisations, networks and alliances. As in all revolutions, the first players to recognise new business opportunities and adopt new practices have the best chance of making gains in market share.
Driving Tekla Structures’ development work for the concrete market BIM solution is its association with the Precast Concrete Software Consortium (PCSC), a group of 13 leading US prestressed and precast concrete companies that joined together to further the development of advanced software solutions (http://dcom.arch.gatech.edu/pci2/news.asp).
They identified that the precast industry could significantly reduce both costs and lead-times by applying advanced modern 3D modelling and data integration technologies.
In a relatively short period of time, the PCSC selected Georgia Tech as technical advisor and programme manager, developed a detailed technical specification, defined a project plan and selected the Tekla product platform as the best choice for future development.
The reason for the adoption of Tekla Structures was said to be the software’s unique ability to model the whole precast concrete building, and not simply to provide a collection of different, and potentially non-matching individual parts. Moreover, allowing for integrated modelling of members, reinforcement and fittings, all parametrically defined, enables design changes to be propagated to members, reinforcement and connections.
Drawing and reports
When adopting Tekla Structures, the drawings and reports are never out of date or contain erroneous information, as they are intrinsically linked to the model. When model changes occur, the drawings are automatically updated to match the modified structure, regardless of whether the drawings were automatically created or manually modified.
The drawing presentation and reports can be defined according to any company standards. The customisable drawing settings, provide full control of the drawing presentation, marking, dimensioning and layouts. Basically everything that is required can be indicated on the drawing. To improve the communication between other design team members, a snapshot of the rendered model can be created, or functionality used to publish the model to our integrated web-viewer, which allows anyone with access to Microsoft’s Internet Explorer (MS ie6) to view the model in a rendered form.
The new technology has finally brought the building and construction industry dream of integrating the different workflow processes attainable by everybody, which will speed up the ongoing slow but inevitable change to the industry. The new way of managing the construction process with BIM is actually the easiest way to go forward. The applications based on the 3D product-modelling thinking already provides remarkable benefits compared to old technology, not to mention the major benefits coming in the near future.
