ИСТИНА

Recently, Building Information Modeling (BIM) technologies and, in particular, BIM servers proceeding with IFC-driven product data have become increasingly important in architecture, engineering and construc-tion (AEC). However, a standard query language for IFC data has not yet been established, which prevents the interoperability between BIM applications and wider adoption of the IFC standard. In the paper require-ments to an IFC query language are summarized with the focus on the compliance and harmonization with data definition and data manipulation languages which generally are the parts of a common data access in-terface. As a result of the study, the IFC query language was proposed and formalized. Using EXPRESS con-structs and JSON structures, the language allows to specify complex predicative queries on object collec-tions and recursive traversing queries on object networks. Explanatory examples of typical IFC queries are provided to illustrate the proposed language and prove its advantages.