With the rapid advancement of Building Information Modeling (BIM) technology and the continuous improvement of BIM-based software tools, BIM is increasingly recognized and adopted by engineering professionals in China. However, market research indicates that architects have embraced BIM technology with greater depth and breadth than structural engineers. This article draws on the author’s practical experience with Autodesk Revit Structure to discuss challenges faced by structural engineers when 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, 3D BIM-based software like Revit uses numerous system and module parameters that differ significantly from traditional 2D drafting methods. Since BIM tools must accommodate both 3D modeling and 2D design conventions, their parameter systems are more complex than those of 2D software. Improper parameter settings or mismatches often cause unexpected issues during use.
Secondly, structural designs often require special components, but if these custom component modules (families) are poorly designed, their 3D models or sectional views may not meet engineers’ needs. Consequently, many structural engineers abandon BIM and revert to traditional 2D drawings.
Additionally, BIM ideally supports bidirectional linking between 3D physical models and structural analysis models. Because analysis models include various parameters such as loads, load combinations, and support conditions required by third-party software, the diversity of parameters increases. This complexity makes it challenging for beginners to quickly master the tool and fully utilize the bidirectional link—one of the most desired features by structural engineers. The following sections propose solutions to these challenges.
2. General Solutions
These solutions mainly target novice users of Autodesk Revit Structure and those working on simple structural projects. The key strategies include:
2.1 Develop Project Templates Aligned with Company Design Practices
A well-crafted project template forms the foundation for efficient BIM modeling. A good template minimizes repetitive work and accelerates design. While Revit Structure provides standard Chinese project templates, these are generic and require customization to fit individual company standards. Key settings include:
(1) A clear, hierarchical view structure in the project browser to facilitate view organization and improve efficiency (see Figure 1).
(2) Custom view templates that set view property parameters to ensure plans meet drawing standards and user habits. For example, structural layout plans should use “Hidden Line” mode, while structural templates and plan views are best presented as “Shading/Edges with borders” for intuitive modeling. View templates control which content is shown or hidden based on their purpose.
Recommended view templates include:
1) Structural foundation plan—for foundation and pile layouts;
2) Structural template plane—for BIM modeling operations;
3) Structural layout plan—for positioning, dimensions, numbering, and annotations;
4) Structural reinforcement plan—for drawing and labeling steel bars in beams, slabs, and columns;
5) Structural section—for detailed sections and annotations;
6) Structural elevation—for slant supports, trusses, and transfer structures.
(3) Add commonly used component types for system and component families. For example, structural wall types with thicknesses of 100, 125, 150, 180, 200, 250, 300 mm, etc.; floor slabs with thicknesses of 100, 120, 150, 200 mm, etc.; foundation slabs of 500, 800, 1000 mm, etc.; and concrete beams and columns with typical dimensions such as 200×400 mm, 300×500 mm, etc. More types can be added based on project needs.
(4) Customize frequently used schedules such as beam size lists, wall and column size lists, staircase schedules, structural floor height tables, and material lists. Below is an example of a beam size schedule.
(5) When creating project templates, it is possible to import types, families, and standards from successful projects. However, templates must be tested for suitability and should avoid excessive families that may not be useful across all projects. A simpler template is generally preferable.
2.2 Create Custom Component Families According to Company Standards
Structural component families include foundations, columns, beams, trusses, and stairs. Industrial design firms often use prefabricated and steel components, while residential design companies primarily use cast-in-place concrete components. Developing component families that comply with company standards and loading commonly used families into project templates can save time and improve performance.
Modifications can be made to the default Revit Structure families, but customization should align with user habits and company standards.
2.3 Organize Common Annotation Symbols and Detailed Drawing Families
Annotation symbols include component tags, connection symbols, section and detail callouts, elevation tags, revision tags, centerlines, and planar annotations. Detailed drawing families cover 2D slab reinforcement layouts, hole openings, steel structure sections, and fill areas. Steel reinforcement families include rebar markers, hooks, and shapes.
Many existing family files are available as references, but only commonly used items should be kept in project templates.
2.4 Develop Company Title Blocks
In Revit, title blocks are 2D annotation families. The recommended process involves using the metric title block as a template, loading a 2D CAD frame into the family editor, aligning it with the template, partially exploding it, and then adding text labels such as owner name, project name, drawing number, scale, revision info, and signatures. After adding these tags, save the family under a new name.
When loaded into projects, some labels automatically link to system variables, while others can be manually edited per drawing. Some edits propagate across all drawings simultaneously.
2.5 Link 2D or 3D Architectural CAD Drawings as Structural Modeling References
Because architectural beam and column families differ from structural ones, it is advisable to use architectural CAD files mainly as references for positioning and then independently build the structural BIM model. Linking these drawings helps provide accurate spatial conditions for structural modeling.
3. Solutions to Advanced Challenges
These solutions target intermediate and advanced users working on complex structural projects.
3.1 Develop Custom Families for Irregular Components
Structural engineers add value by solving unique design problems, offering alternative solutions, and ensuring spatial compatibility with architectural and MEP requirements. This often involves irregular components such as folded beams, variable cross-section beams, notched beams, fish-belly beams, openings, diagonal columns, special-shaped columns, SRC composite elements, and local drop plates.
Most BIM tools do not provide families for such irregular components. Using standard components instead defeats BIM’s core purpose, as conflicts may go undetected or false clashes may arise. Creating flexible, intelligent families for irregular components is essential for effective BIM application.
This process requires strong 3D knowledge, computer skills, structural expertise, and the ability to learn and innovate. Although creating these families is a large undertaking, investing effort upfront saves significant time later. Due to space constraints, detailed instructions are not provided here.
3.2 Flat Representation of Reinforced Concrete Structures
In mainland China, reinforced concrete construction drawings typically use flat plan representations with codes, which construction workers translate into process or layout drawings. This approach reduces drawing effort for structural engineers.
Initially, Revit favored automatic extraction of process drawings from BIM models, considering flat representation redundant. However, this conflicts with Chinese engineers’ habits and regulatory requirements for construction document submission.
To address this, Autodesk Subscription offers flexible solutions for flat representation in Chinese structural drawings, using shared parameters and 2D details. The author has tested this approach and finds it feasible, though it does not significantly improve efficiency compared to traditional 2D annotations and still has room for enhancement.
3.3 Linking and Managing BIM Physical and Analytical Models
Revit Structure integrates with many third-party analysis tools, with ETABS being the most familiar to Chinese users. However, version mismatches often prevent smooth synchronization, so bidirectional linking between physical and analytical models is rarely utilized.
If analytical modeling is not used or accuracy is less critical, disabling analytical features can significantly improve model performance. Refer to the user manual for instructions on disabling these features.
3.4 Reinforcement and Steel Structure Node Details
While Revit Structure supports reinforcement and steel node details through built-in features and 2D detail families, third-party add-ons can greatly accelerate drawing production. The structure extension program available via Autodesk Subscription is one such tool, though it still needs functional improvements.
4. Phased Implementation of BIM in Structural Design
During early and preliminary design phases, BIM facilitates coordination with architects and MEP engineers, allows flexible alternative solutions, and provides 3D visualization for client decision-making. Current BIM tools adequately support preliminary design requirements.
Structural engineers, however, focus on generating compliant design and construction documents quickly from structural calculations. Due to unresolved technical challenges, seamless transition from 3D models to traditional construction drawings is not yet fully achievable.
Therefore, phased or partial BIM adoption is recommended to boost efficiency. For example, quickly creating 3D models and exporting floor plans and sections as condition diagrams not only supports other disciplines but also serves as a reference for reinforcement and detail drawings in 2D software like AutoCAD. Unnecessary layers can be turned off in these 2D drawings.
When design updates occur, only the condition diagram needs re-exporting and overwriting, automatically updating all associated reinforcement and detail drawings. This avoids repeated manual edits.
5. Summary
(1) Establish unified company BIM standards and project templates to help beginners ramp up quickly and enhance coordination within and across design teams.
(2) Creating custom families for irregular components is essential for structural engineers to fully leverage BIM technology.
(3) Adopting flexible solutions and phased BIM implementation allows early benefits and boosts competitiveness.
(4) Forming internal BIM teams to share experiences and solutions promotes deeper and broader BIM adoption, yielding significant benefits.
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