# Research on 3D Digital Technological Process of Construction Products with Model-Based Definition
## 4 Application Examples and Discussion
### Infill Wall Masonry Process Information Expression
#### 4.2.3 Infill Wall Masonry Process Information Expression  
1. Infill wall masonry process design model processing  
The filling wall masonry process design model established in Section 4.2.2 is exported to the sat file, and the file is imported into the CATIA Composer platform to read the geometric information in the design model. Then, the same type of building parts (beams, slabs, columns, etc.) in the platform is selected to create a selection set, the texture, material, name, brightness, opacity, and other information of the building parts in the attribute panel are mapped, and the parts of the operation process are simulated. The completed filling wall masonry is illustrated in Figure 6.  
Figure 5: Modeling of masonry tie bars. Figure 6: Treatment of the infilled wall masonry model. Creation of the infill wall masonry key view  
The key frame view is created according to the detailed technological process. By setting the explicit and implicit model components in the view and fully utilizing the feedback and interaction of the three-dimensional model to the information, the quality control points of the process and the steps, the details of the node practice, and the construction sequence and the mandatory requirements are displayed to simulate the dynamic construction process. The collection of some key views is shown in Figure 7.  
3. Infill wall masonry process information mapping  
Taking the filling wall masonry key view (wall tie bar planting bar) as an example, the three-dimensional model in the view originates from the process design model of the current construction process. Meanwhile, the quality and technical control points of the planting bar are expressed by the annotation method (the yellow text box), and the detailed structure is explained by the mapping (the construction details). The relevant standard specifications are linked (the white text box) to facilitate in-depth understanding and research, as shown in Figure 8.  
Continuous key views can express dynamic process operations, as shown in Figure 9. Therefore, the filling wall masonry 'three-one masonry' process content can be expressed through multiple continuous key views. Figure 7: The set of key views of the infill wall masonry construction technology: (**a**) preliminary stage; (**b**) tie-bar implanting in wall; (**c**) wall masonry; (**d**) flatness check. 4. Export the key view of infilled wall masonry  
After the process information of the masonry infill wall is attached, the key view is exported to a variety of format files, such as exe and smg, on the CATIA Composer platform. Then, these files can be directly published to PDF, HTML, and other formats for viewing. Specifically, the exported exe file can run directly in the Windows system without the limitations of the software platform and achieve the same function as the software platform. Figure 8: Process mapping of key views for planting a reinforcing bar in the wall. Figure 9: Three-one masonry key views: (**a**) the first step of masonry; (**b**) the second step of masonry; (**c**) the third step of masonry; (**d**) the fourth step of masonry. The derived smg format can be used for secondary development based on the Composer Player ActiveX control provided by the CATIA Composer platform. 5. Formation of an interactive construction instruction book for masonry infill wall  
The VBA language based on the Excel platform calls the Composer Player ActiveX development control, imports the three-dimensional interactive view, processes information in the platform into the work instruction book based on the Excel platform, and compiles the process and process instructions according to the process information of the infilled wall masonry in Supplementary Materials. Specifically, the three-dimensional interactive view can be directly controlled in the view playback area created by the Excel platform, and the VBA macro-code can be used to create command buttons for view control. In addition, the lightweight process information expression program is also linked in the view control area.