BUILDING INFORMATION MODELING – BIM
Building Information Modeling (BIM) is a new process to produce a building that can embrace all its life cycle. Presupposes the construction of a tridimensional model, covering the object information to be built. In this sense, one can use it to obtain geometric data, planning data, quantification data, building data and post-building data. In face of the range this process can act, it must cause many impacts on all of the productive chain and, as a result, many forms of labor should be reviewed or changed.
The oldest known document that brings the first concepts of BIM is an article published by the extinct AIA Journal in 1975 by Charles M. Eastman (EASTMAN, et al., 2008). It defined some isolated concepts as interactivity of project elements, automatic update of drawings, data consistency in projects, simplified cost estimation generation, rules and precepts verification in projects and also the advantages in the buildings planning.
Building Information Modeling (BIM) is oficcialy translated in Brazil (NBR/ISO 12006-2 and NBR 15965) as Modelagem da informação da Construção.
The advance of BIM in the world is real. The series of surveys made by McGraw-Hill Construction portrays that the levels of BIM’s adoption in the U.S. has grown from 28% in 2007 to 49% in 2009, reaching 71% in 2012 (McGRAW-HILL CONSTRUCTION, 2012). It indicates a strong tendency of growth in this work process. Other data recently published by McGraw-Hill Construction informs about tendencies in the use of BIM in the world and in Brazil. In Europe, for instance, 41% of the hiring companies in the civil construction area have been using BIM for three to five years. In Japan they are 80% and in Australia 50% of the companies. In Brazil, 40% of the companies that have answered the survey are in the middle of the implementation process of BIM and 70% of them have been using BIM for one to two years (McGRAW-HILL CONSTRUCTION, 2014). Some bids for projects hiring and constructions are already taking place in Brazil, as the case of the Operational Unit of Santos Bay, projects in São Paulo’s subway and others.
BIM is based on a parametric tridimensional model which contains information to be used during the whole life cycle of the edification by different actors (architects, engineers, consultants, estimators, builders, operators, maintainers).
Although BIM is not a technology or an application, one depends on certain technologies and tools, such as specific hardwares and softwares, to model and other needs.
To use BIM’s best potential, one needs to have the goal clear and use in the construction. For instance, for contractors it is useful for some goals, such as reduction of errors and building alterations, updated and trustful information management and the building maintenance. On the other hand, for drafters, it is suitable for the trustfulness on the produced documentation, anticipation of problems, assertiveness and guarantee of better solutions.
There are many uses of BIM, depending on the stage of the life cycle of the edification in which it is applied. For example, in the stage of conception, the model may be used for the creation and conception with mass studies, Earth movement studies and the visualization by the client. In the actual stage of the project, it can be used for parametric 3D modeling, norms and codes validating, 3D coordination and interference detection, simulation and analysis (energetic structure, acoustic, illumination, climate control and others) and generation of documentation.
In the building planning stage, the use of BIM is focused on the quantitative extraction, 4D planning and, finally, financial and physical schedule. In the phase of building, the main uses of BIM are planning and occupation of the construction site, the pre-manufacturing and digital manufacturing, control, 4D and 5D planning and “as built”. In the post-delivery stage, it is used mainly for programming and preventive maintenance of the building, the analysis of building systems, the management of the building, plans for reform, and, finally, planning of the abandonment of the building (its demolition considering the reuse of materials, it is, recycling).
To build a BIM model, not only the goals and uses of BIM should be considered, but also the requirements of the project must be clear and agreed between all the parts involved. The information must be objective so that it can make the virtual building the reality of the construction. BIM model must be constructed based on the object information, it is: walls, windows, doors, beams, pillars. For these elements to fit the model, they must be editable (parametric). In other words, they must be able to be submitted to edition of parameters, such as dimensions, materials and others. These objects should compose what we call BIM library and may be attached to BIM software or not. Many libraries can be built by the products manufacturers and be available on the internet or by the own project or construction office, besides the ones that are already included in the BIM softwares.
Nowadays, there is a comission of the current ABNT Norms, number ANBT/CEE-134: Comission of Special Study – Building Information Modeling, stablished in 2009. It has published the following norms:
- NBR ISO 12006-2:2010 Building Construction — Organization of information of the construction Part 2: Structure for the information classification
- NBR 15965-1:2011 Building information classification system Part 1: terminology and structure
- NBR 15965-2:2012 Building information classification system Part 2: Building objects characteristics
- NBR 15965-3:2014 Building information classification system Part 3: Construction Processes
In Brazil we still have a great path ahead of us to implement BIM, although one can find some project companies that have already adopted the process and are currently working in this way. On the field of building and construction companies, we can observe the intention and some isolated attempts of implementation, with some cases of success presented in seminars and in articles on technical magazines.
We hope that the market takes advantage of this intercrop period and take this moment as an opportunity to recycle and improve on all fields, including in BIM, so that we can soon reach new levels on the building and project execution.
ARCHT. MIRIAM ADDOR
Addor & Associated Chief Executive
Text developed for ABECE magazine (Brazilian Association of Engineering and Structural Consultancy).
 American Institute of Architects