With the rapid advancement of Building Information Modeling (BIM) technology and continuous improvements in BIM-based software tools, BIM is gradually gaining recognition and application among Chinese engineering professionals. Market research indicates that architects currently demonstrate a much deeper and broader acceptance of BIM technology compared to structural engineers. Drawing from the author’s practical experience with Autodesk Revit Structure, this article addresses the challenges faced by structural engineers in applying BIM technology. It also explores effective methods, processes, technical approaches, and solutions for implementing BIM in structural engineering design.
1. Challenges in Applying BIM Technology for Structural Engineers
Firstly, BIM-based 3D software tools like Revit use numerous system and module parameters, which differ significantly from traditional 2D drawing techniques. To maintain coherence with 2D design habits, these parameters are far more complex than those in 2D software, often leading to unexpected issues caused by improper parameter settings or mismatches.
Secondly, structural design often requires specialized components. If these custom component modules (families) are not well designed, their 3D and sectional views may fail to meet engineers’ expectations. This frequently results in structural engineers abandoning BIM technology and reverting to traditional 2D drafting methods.
Additionally, the ideal BIM workflow involves a bidirectional link between the physical 3D model and the structural analysis model. However, because the analysis model includes a variety of parameters required by third-party software—such as loads, load combinations, and support conditions—the software parameters become more diverse and complex. This steep learning curve hinders beginners from fully leveraging the bidirectional connection, a feature highly desired by structural engineers. The following sections discuss solutions to these challenges.
2. General Solutions
These solutions primarily target novice Autodesk Revit Structure users and those working on simpler structural projects. Key approaches include:
2.1 Develop Project Templates Aligned with Company Design Practices
A solid project template forms the foundation for efficient BIM modeling by reducing repetitive tasks and accelerating design work. Although Revit Structure provides standard Chinese project templates, they often require significant customization to suit individual company workflows. Essential template settings include:
(1) A well-organized hierarchical view structure in the project browser (see Figure 1) to facilitate view management and improve efficiency.
(2) Customized common view templates:
Set view property parameters to ensure plan views comply with drawing standards and company preferences. For example, use the “Hidden Line” display mode for structural layout plans and “Shading/Edges with borders” for structural and plan templates to enhance modeling clarity. In brief, view templates control which content is displayed or hidden based on their intended purpose.
Suggested view templates include:
1) Structural Foundation Plan: for foundation and pile layouts;
2) Structural Template Plane: main working view for BIM modeling, complemented by 3D views for verification;
3) Structural Layout Plan: for annotation of component positioning, dimensions, numbering, and notes;
4) Structural Reinforcement Plan: for detailing steel reinforcement in beams, slabs, and columns, including labeling and quantity annotation;
5) Structural Sections: for detailed sectional views and related annotations;
6) Structural Elevations: for representing slant supports, trusses, and transfer structures.
(3) Add common component types to system and component families:
Recommended structural wall thicknesses (in millimeters): 100, 125, 150, 180, 250, 300, 350, 450, 500, 600, 700, 800, 900, 1000;
Structural floor slab thicknesses: 100, 120, 150, 180, 200, 220, 250, 300, 350, 400, 500;
Foundation plate sizes: 500, 800, 1000, 1500, 2000, 2500;
Common concrete beam sizes: 200×400, 300×500, 400×600, 500×600, etc.; more can be added as needed.
Similarly, a variety of concrete column types should be included.
(4) Customize commonly used schedules:
Typical schedules for structural engineers include:
1) Component size schedules (beam, wall, column dimensions);
2) Staircase schedules;
3) Structural floor height tables;
4) Material quantity lists.
Below is an example of a beam size schedule.
(5) Notes on creating project templates:
Revit allows transferring types, component families, and standards from completed projects into new ones, enabling partial reuse of successful templates. However, these templates must be validated for suitability in your own projects. Avoid overloading templates with unnecessary families that may not be relevant to all projects. It is generally better to maintain streamlined templates for better efficiency.
2.2 Develop Common Component Families Aligned with Company Standards
Structural component families typically include foundations, columns, beams, trusses, and stairs. Companies focusing on industrial buildings often use prefabricated or steel components, while residential building designers rely mostly on cast-in-place concrete components. Creating and maintaining component families that reflect company standards saves time and improves consistency. Load commonly used families into project templates to reduce file size and enhance performance.
Component families can be customized by modifying existing Revit Structure families. The key is to tailor these to your company’s design practices and preferences.
2.3 Organize Common Annotation Symbols and Detailed Drawing Elements
Annotation symbols include component tags, connection symbols, section markers, detail indices, elevation markers, revision tags, centerlines, and planar annotations.
Detail drawing elements cover 2D slab reinforcement, openings, steel structure sections, and filled areas.
Structural steel reinforcement annotations include rebar markers, hooks, and shape representations.
While many annotation and detail families are available, it is advisable to retain only those frequently used in your project templates.
2.4 Create Company-Specific Title Blocks
In Revit, title blocks are 2D annotation families. The recommended process is:
- Use an existing metric title block as a template.
- Load a 2D CAD frame into the family editor.
- Align it with the title block template frame and partially explode the CAD frame.
- Add text tags such as owner name, project name, project number, drawing name, design stage, scale, drawing number, designer signature, revision version, and revision date.
- Save the customized title block under a new name.
When loaded into projects, some labels automatically link to system variables, while others can be edited independently per drawing. Changes made on one drawing may propagate to others depending on the label’s configuration.
2.5 Link 2D or 3D Architectural CAD Files as Modeling References
Because architectural beam and column families differ from structural ones in Revit, it is recommended to use 2D or 3D architectural CAD files solely as references for structural modeling. Structural BIM models should be built independently based on these linked files, which mainly provide component positioning.
3. Solutions for Advanced and Complex Issues
These solutions address intermediate and advanced users working on complex projects:
3.1 Create Custom Specialized Component Families
Structural engineers add value by proposing multiple structural solutions that meet architectural spatial requirements and accommodate mechanical and electrical installations without conflicts. This often requires custom components such as folded beams, variable cross-section beams, notched beams, fish-belly beams, beam openings, diagonal columns, special-shaped columns, SRC composite members, and local drop plates.
Most BIM tools don’t provide predefined families for these irregular components. Using standard components to approximate these shapes diminishes BIM’s core advantage, as simplified models fail to detect true clashes and generate false conflict warnings. Therefore, creating custom families for irregular components is essential for effective BIM application.
Designing these families demands comprehensive knowledge of 3D modeling, strong computer skills, structural engineering expertise, and a willingness to learn and innovate. Although it is a large and systematic task, focusing on commonly used irregular components tailored to a design team’s needs can save significant time in the long run. Detailed instructions for creating these families are beyond the scope of this article.
3.2 Flat Representation of Reinforced Concrete Structures
In mainland China, reinforced concrete construction drawings often use flat (planar) representation with coded annotations. Construction workers then translate these plans into process or layout drawings, minimizing the drafting workload for structural engineers. While Revit Structure initially viewed flat representation as redundant—since BIM models can automatically generate process and layout drawings—this approach does not align with Chinese engineers’ habits or government approval requirements.
To address this, Autodesk Subscription offers flexible solutions for flat representation through localized toolsets featuring shared parameters and 2D detail families. The author’s preliminary tests indicate this approach is feasible and effectively addresses flat drawing requirements. However, efficiency gains compared to traditional 2D annotation remain limited, indicating room for further improvement.
3.3 Linking and Managing BIM Physical and Analytical Models
Although Revit Structure supports linking with various third-party analysis software, ETABS is the most widely used and familiar among Chinese users. Version synchronization issues between Revit and third-party tools often limit the practical use of bidirectional links, leading many users to forgo this feature.
If analytical modeling is not critical, disabling these features can significantly improve model performance. This can be done via the user interface or by modifying the Revit Structure.ini file. Refer to the official user manual for detailed instructions.
3.4 Reinforcement and Steel Structure Node Detailing
While Revit Structure can create reinforcement and steel node details using internal tools and external 2D detail families, third-party extensions can greatly enhance drafting speed. Autodesk Subscription’s structural extension is one such tool, though it still requires functional improvements.
4. Phased Application of BIM in Structural Design
During early structural and preliminary design phases, BIM facilitates coordination with architects and MEP engineers, offers multiple alternative solutions, and enables visualization for client decision-making. Current BIM tools adequately support the depth required for preliminary design documentation.
However, structural engineers prioritize the workflow from structural calculations to rapid production of construction documents adhering to standards. Due to unresolved technical challenges in current BIM tools, seamless transition from 3D models to traditional construction drawings is not yet fully achievable. Therefore, phased or partial BIM adoption is recommended to enhance efficiency.
For example, creating 3D models quickly to generate floor plan structure diagrams and sections (template drawings) provides a reliable base for other disciplines. Exporting these as 2D condition diagrams allows their use as references in reinforcement and node detail drafting with 2D software (e.g., AutoCAD). Turning off unnecessary layers in reinforcement and detail drawings streamlines the process.
When design changes occur, simply re-export and overwrite the condition diagrams to automatically update related reinforcement and detail drawings, avoiding repetitive manual revisions.
5. Summary
(1) Establish unified company BIM standards and project templates to help beginners quickly get started and facilitate coordination and resource sharing within and across design teams.
(2) Developing custom families for irregular components is essential for structural engineers to fully leverage BIM technology.
(3) Employing flexible solutions and phased BIM adoption enables early benefits and enhances competitive advantage.
(4) Forming an internal BIM technology team to share experiences and collaboratively solve problems promotes deeper and wider BIM adoption, bringing significant benefits.
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