## 4 Naming Process for Bridge Components
### Basic Bridge Geometric Modeling and Information Reassigning
For example, while a crossbeam and the main girder of the bridge can be identically represented as physical objects, these elements clearly have different functions, which require that the quantity take-off is considered separately for these two elements. Therefore, the process of applicability verification of the bridge information model in this study was as follows. (1) The bridge information model was generated using BIM authoring software. (2) The semantic information concerning the necessary bridge components was generated by the user, using Figure 8 or Algorithm 1. (3) Identifiers of the members were generated using the automated naming method. (4) The model applicability based on the bridge components and identifiers was examined. (5) Using the generated IPF, the semantics-based model regeneration of bridge components was examined. ### IFC-Based Model Implementation of a Steel Box Girder Bridge Structure

To examine the applicability, some parts of the real steel box girder bridge were modeled using developed IFC and user-defined PSETs in this study. Figure 11 shows the standard cross section and current endpoint of the steel box interval of the target bridge that was modeled. The actual bridge consists of a total of 34 spans, and has a length of 1441 m. In this study, two span intervals were examined, with each span being 50 m. Figure 12 shows the result of the detailed design-level modeling based on the design drawings. As shown in the figure, each bridge component contains a corresponding identifier. Basically, the process of generating such information entails repetitive manual operations. In this study, we could reduce the information-generating time through multi-selection of objects as well as the use of applied object libraries (in the case of Autodesk-Revit families) that include the basic and shared data. Figure 13 is the IFC-based bridge information model generated through the integration of geometric model and semantic identifiers in accordance with a process of Figure 6:3 The model objects and properties have been checked via Solibri Model Checker. Additional information on identification could be found on the info tab with the name of the PSET. Figure 6:4 Drawings of a sample steel box girder bridge. Figure 6:5 The result of the detailed design-level bridge information model. Figure 6:6 Steel box girder bridge information model based on the IFC with _Pset_SteelBoxBridgeComponentsIdentification_. ### Quantity Take-Off Check Using the Bridge Data Model

The basic quantity take-off was derived using the steel box girder bridge information model, and the result was compared to the design drawings for that bridge. Table 4a shows part of quantities specified in the design drawings, while Table 4b shows the quantities corresponding to the components in Table 4a, calculated using the information model. Functions provided by Revit were used for the quantity take-off based on the information model. In terms of the quantities of each component, the results were identical. However, the quantity take-off results were provided in a faster and more detailed manner, as compared with the previous method of using the design drawings. The specific name of each component, as well as the corresponding quantity and quantity, can be provided in a specific form. For example, compared to \"Horizontal stiffener\" in Table 4a, \"Horizontal stiffener\" in Table 4b is separated into two elements. Nevertheless, while comparing the results, it was noted that the representation of components differed between the users, requiring additional manual tasks for adequately identifying the components.