BIM is a broad concept: it is a relevant approach to designing, constructing and operating an architectural object in a single information ecosystem that depends on multiple aspects of its lifecycle. Each of these stages involves different organizations that create documentation in the form of separate files and different applications, which is often fraught with losing or distorting them during long-term storage and transfer to other performers, incompatibility of different applications. This results in significant time and financial resources being wasted.
CERTIFICATION & IFC
The practice of certifying Information Models has begun to be implemented not so long ago. There are already requirements according to which they are verified.
We have experience in passing the Moscow State Expert Examination. Building Information Model BIM coordination was performed by us. It should be noted that the state authorities do not have access to foreign software, nor can they impose the use of a particular application on the contractor. Therefore, the expert performs checks in a specially created program that can only check models in IFC format, in order to enable «communication» between the designer and the expert.
Of course, this affects the work of the BIM department. The contractor prepares the 3D view for export to the IFC format. He checks whether all the information is filled in according to the requirements for the model.
In addition, it is necessary to work out mapping — mapping of parameters. The names of the parameters can be different in the native format and in IFC. The main thing is to specify what the parameters should look like and what category the element should belong to when setting up the export. The exported model should be checked for the presence of all elements and parameters.
There may be wrong settings somewhere. Or there may be an error in the mapping. I was unable to set up a working mapping the first time, as this was my first experience.
As a result, the appearance of the model in native format was not important to the reviewers because the view set up for export to IFC included only the model element parameters described in the information model requirements.
IFCS ARE NOT IDEAL
Comments regarding the Information Models were received in a formatted text document. Whether or not each requirement was met was indicated. For the availability of information in the model, a percentage information content table was provided. A standard clash matrix was also made available, with a supplement listing the types of clashes identified.
All our questions were answered very quickly thanks to the work of the reviewers. In several viewer programs it is possible to check the IFC. However, the problem is that it takes a long time to load the model in such a program. Not all programs are able to view the model quickly due to slow work. Sometimes, due to IFC errors, not all elements are exported. For example, a wall may be missing and the only way to find it is to manually find it, re-export it, and double-check it. Sometimes some elements change their geometry during export, causing additional collisions that should not exist.
At this stage of development, there are some peculiarities to the format. That is the reason for the longer validation time. However, thanks to the advantages of the open format, its usage is becoming more and more prevalent in the professional world.
Interoperability is the ability of two or more information systems or components to exchange information with each other and to make use of the resulting information. It helps an expert to see our model in his program differently. Internal agreement is also helped by this capability.
E.g. an architect can use Archicad and a structural designer can use Revit. Typically, for the designer to see the development of architectural solutions, the architect must convert his model to IFC and the designer must download it.
IFC can also help in cases where designers have not agreed on the version of the program they are working in, and the one who has an older version cannot see his colleague’s developments.
The solution: export the IFC model from the model created by the application of the older version and then import the model into the application of the newer version.
RELEVANCE OF IFC
The relevance of IFC is increasing due to the fact that design companies are switching to Russian software, because it is not possible to restructure their work in one day: someone will continue to work with the previous software, maybe there will be new programs, better than the previous ones. That is why it is worth to pay attention to the described format, which will help in «communication» in one language.
