Structural Analysis
Phân tích kết cấu
Export the structural BIM model to analysis software to calculate forces, verify design codes, optimize sections, and detect problems early.
Common tools
ETABS, Robot Structural Analysis, RFEM
Value delivered
Reduces verification time and discrepancy between design model and analysis model
Adoption in Vietnam
Common in Vietnam but often a separate workflow — direct Revit↔ETABS linking still limited.
Level of Information Need (LOIN)
G = Geometry · A = Alphanumeric · D = Documentation (ISO 7817-1:2024 method). A blank cell means this use sets no specific requirement for that discipline/stage.
| Discipline | Concept | Schematic | Developed | Technical | As-built / Operation |
|---|---|---|---|---|---|
| Architecture | — | — | — | — | — |
| Structure | — | G2·A2·D1 | G3·A2·D1 | — | — |
| Mechanical | — | — | — | — | — |
| Electrical | — | — | — | — | — |
| Plumbing | — | — | — | — | — |
Critical stages: Schematic · Developed
Rationale: STRU-only use. A2 is the hard requirement and must be met as early as ST2 — material grades, section sizes, loads and support conditions are all needed for the analytical model; geometry alone (even G3) is insufficient. G2 at schematic is acceptable because the analytical model abstracts members centrally. D1 references the applied design codes (TCVN 2737, TCVN 5574, Eurocode 2/3/8).
What it really is
Structural analysis separates an analytical model — an idealised system of members, plates and nodes used to solve internal forces — from the physical model containing the real geometry of beams, columns, slabs and walls in Revit, then sends that analytical model to dedicated calculation software to solve forces and check capacity and deflection against the applicable design code. The two models are not the same object: the physical model describes true member dimensions for drawings and quantities, while the analytical model describes idealised centrelines, connections and supports for solving the structural problem. Revit auto-generates the analytical model from the physical model when a member is placed, but it does not keep the two in sync forever — once the physical model is edited afterwards (a grid shifted, a section changed) without re-running the sync, the analysis keeps using the stale analytical model and produces results that no longer reflect the real building. Unlike simply "running structural software" as an isolated step, BIM-based structural analysis is a closed loop: export the analytical model, assign loads and load combinations per TCVN 2737:2023, assign the correct connections and supports, solve and check the code, then bring the chosen sections back into the physical model so architecture and MEP coordinate against updated geometry. The core value is not faster calculation but that the physical model and the calculation results never drift apart through repeated design iterations.
When to use
Worthwhile for every project subject to mandatory BIM under Art. 8(1)(a) (Grade II and above), especially multi-storey or long-span structures, complex wind or seismic loading, and projects with many iterations of section changes between architecture and structure. For small, structurally simple projects with few design changes, hand calculation or a standalone analysis package without a BIM link can still be enough — the cost of setting up a Revit-to-analysis-software link only pays off once the number of iterations is large enough to recover the setup effort.
Prerequisites
- •A physical structural model from Design Authoring at a LOIN sufficient for analysis: beams, columns, slabs and walls modelled as true structural objects, not generic models, with preliminary sections and materials
- •The applicable load standard and load combinations settled in the EIR/BEP — at minimum TCVN 2737:2023, plus the material-specific TCVN standards (reinforced concrete, steel, timber...)
- •A structural engineer competent in both Revit and the chosen analysis software, who understands the distinction between the physical and analytical models
- •An internal QA process that mandates checking results by hand calculation or by an independent checking engineer before the calculation report is issued
- •A contract or BEP stating who is responsible for syncing chosen sections back into the physical model once analysis is complete (Art. 8(2))
Inputs
Structural task team · .rvt / IFC
Lead structural engineer · appointing party (via the design brief) · .pdf
Appointing party · lead appointed party · .pdf / .docx
Survey task team · .pdf
Other task teams · IFC / .rvt
Structural task team · gắn trong mô hình
Outputs
Analytical model that has run and passed the code check
định dạng nội bộ phần mềm phân tích (.rtd / .edb / .fem) → Structural engineer · BIM Coordinator
Accepted when: Meets the safety factors of the applicable code; no outstanding analytical-to-physical model deviation warning beyond tolerance
Structural calculation report with load combinations per TCVN 2737:2023
.pdf → Appointing party · appraising authority
Accepted when: Sufficient data for hand-calculation cross-check: loads, combinations, connections, supports, key force results
Physical model (Revit) updated with sections per the analysis result
.rvt / IFC → Architectural and MEP task teams
Accepted when: Sections match between the model and the calculation report; no member is left at a stale preliminary section
Appraisal submission package with BIM data
IFC hoặc định dạng mở khác → Competent construction authority
Accepted when: Provided as the open IFC standard or another open format suited to the project's nature; the competent authority may additionally request the native format for cross-checking (Decree 217/2026/NĐ-CP, Art. 8(3)(a) and (b))
General workflow
Prepare the physical structural model
Verify the structural model from Design Authoring uses true structural object types rather than generic models, with material properties and preliminary sections in place. Revit can only generate a correct analytical model when the physical objects are of the right type.
Structural task team · Revit → Physical structural model ready for analysis
Build and export the analytical model
Run the analytical-to-physical model consistency check to flag analytical lines that drift from the real geometry beyond tolerance, then export the analytical model to the analysis software via a direct link or an intermediate format.
Structural engineer · Revit · Autodesk Robot Structural Analysis Professional (direct link) · ETABS / SAP2000 / RFEM (via an intermediate format, where the office already relies on that software) → Exported analytical model matching the physical model
Assign loads and combinations per TCVN 2737:2023
Assign dead, live, wind and seismic loads per TCVN 2737:2023 and the related material-specific TCVN, then set up the correct load combinations by limit state — do not keep the software's default combinations, which are usually written for a foreign code.
Structural engineer · Autodesk Robot Structural Analysis Professional · ETABS / SAP2000 / RFEM → Analytical model with loads and combinations assigned
Assign connections and boundary conditions
Verify and assign the correct connection type (fixed, pinned, elastic) and supports at every node. This is the step most often skipped, because the software auto-assigns defaults on import, and those defaults rarely match the real design.
Structural engineer · Autodesk Robot Structural Analysis Professional · ETABS / SAP2000 / RFEM → Analytical model with connections and supports matching the design
Run the analysis and code check
Solve internal forces and check capacity, deflection and drift against the applicable design code, then iterate a few rounds to optimise sections before settling on a solution.
Structural engineer · Autodesk Robot Structural Analysis Professional · ETABS / SAP2000 / RFEM → Analysis results and proposed sections
Check results by hand calculation
Independently check a few key figures — support reactions, deflection, vibration period — by hand or in a separate spreadsheet, against engineering judgement, before accepting the software result. Without this step, an error from a wrong load or connection assignment flows straight into construction drawings undetected.
Independent checking engineer · lead structural engineer · Independent check spreadsheet, not the primary analysis software → Independent sense-check record of the analysis results
Bring the sections back into the physical model
Update the chosen sections and reinforcement from the analysis software back into the correct objects in the Revit physical model, so architecture and MEP coordinate against updated geometry instead of a disconnected calculation sheet.
Structural engineer · Revit · Autodesk Robot Structural Analysis Professional → Physical model updated with final sections
Run a final consistency check and publish
Re-run the analytical-to-physical consistency check one final time, export the calculation report with the model, then publish to the CDE so the appointing party and other disciplines work from a single shared version.
BIM Coordinator · structural engineer · Revit · Forma Data Management (CDE) → Published model and calculation report
Diagram
↺ When the physical model changes afterwards, return to the export step — the two models do not stay in sync on their own
Common pitfalls
The analytical model no longer matches the physical model after architecture or structure edits — a grid moves, a section changes, but the analysis still runs on stale data
Cause: Editing the physical model without re-syncing the analytical model, and never running the consistency check
Fix: Make the analytical-to-physical consistency check mandatory on every sync, before re-running the analysis
Wrong connection or support assignment — treated as fixed when it is actually pinned, or a boundary condition is missing — pushing forces and displacements far from reality
Cause: Automated import misreads the connection type, or the engineer keeps the default without checking each node
Fix: Manually verify every important connection and support after exporting the analytical model, cross-checked against the structural design documentation
Trusting the analysis software's output outright without a hand-calculation check, so an error is not caught until construction
Cause: Schedule pressure and no mandatory independent sense-check step
Fix: Require a hand-calculation or independent check step (reactions, deflection, vibration period) before the analysis results are submitted for approval
Load combinations do not follow TCVN 2737:2023 — the zone-specific wind or seismic combination is missing, or the software's default combinations are used unchanged
Cause: The analysis software defaults to a foreign code and is never reconfigured for TCVN at the start of the project
Fix: Configure the TCVN 2737:2023 load standard and combinations explicitly when the project is set up, and re-verify before every analysis run
Sections re-selected in the analysis software are never synced back to Revit, and architecture and MEP keep coordinating against the old sections
Cause: No controlled back-sync step, and no one is clearly assigned the responsibility
Fix: State in the BEP exactly who is responsible for updating sections back into the physical model, and when it is published to the CDE
Measuring effectiveness
Compare structural material cost (concrete, reinforcement) between the initial design and the design after automated optimisation iterations, on the same building
Benchmark: Average 8.77% (range 3.21%-13.5% per floor) across 11 case studies of reinforced-concrete buildings, using Revit combined with Dynamo to automate beam-slab design iteration — a small study sample, not a guarantee for every structural type
Compare the time from having a physical model to a ready-to-run analytical model, between manual rebuilding and direct export/sync from Revit
Benchmark: no independent benchmark — set an internal target
Count mandatory re-syncs during a design stage, cross-referenced against recorded design changes on the CDE
Benchmark: no independent benchmark — set an internal target
Key members (beams, columns, slabs, footings) independently hand-checked divided by the total number of key members, before the calculation report is issued
Benchmark: no independent benchmark — set an internal target
Legal basis
There is NO specific requirement for structural analysis in Decree 217/2026/NĐ-CP — this use falls under Article 8 generally. Art. 8(1)(a) makes BIM mandatory for new-build works Grade II and above, from the feasibility study or economic-technical report stage; Art. 8(2) assigns scope, content and information requirements to the contract — the basis for bringing structural-analysis requirements, the applicable load standard (TCVN 2737:2023) and the responsibility for syncing the analytical and physical models into the EIR and BEP; at appraisal, BIM data is provided as the open IFC standard or another open format suited to the project's nature; the competent authority may additionally request the native format for cross-checking (Decree 217/2026/NĐ-CP, Art. 8(3)(a) and (b)). The load and structural-calculation standard sits in the TCVN system, outside the scope of Decree 217 — binding the BIM-based structural analysis workflow (Revit-to-analysis-software linking, model sync) requires writing it explicitly into the contract or BEP; it cannot be inferred from Article 8.
Sources
Only official sources (legislation, standards) and peer-reviewed academic work are cited. No vendor marketing figures or press sources. Reference only — does not replace legal advice.