STAAD.Pro Analysis

Instructions

Linear Static Analysis (two steps)

1. cmd.PerformAnalysis(printOption) — adds the PERFORM ANALYSIS command. Call ONCE only.
2. staad.SaveModel(True) + staad.AnalyzeEx(1, 0, 1) — saves the file, then runs the solver.

Both steps are required. PerformAnalysis alone does NOT run the solver.

Running the Solver — prefer AnalyzeEx

AnalyzeEx is the preferred solver function — it returns a status code and runs both analysis and design. AnalyzeModel is a simpler alternative with no return value (analysis only, no design).

cmd = staad.Command
staad.SetSilentMode(True)
staad.SaveModel(True)
status = staad.AnalyzeEx(1, 0, 1)  # silent, visible, waitTillComplete
staad.SetSilentMode(False)
# status: 2=OK, 3=warnings, 4=errors, -1=terminated

Analysis Messages (Requires STAAD.Pro v26+)

After a run, retrieve the solver's error/warning text. These COM functions exist only on STAAD.Pro v26+ — confirm the connected instance's version from list_instances / get_status before calling (see staad-core → Version Compatibility). On older STAAD they raise an "update STAAD.Pro" error.

These methods live on the root staad object.

errors = staad.GetAnalysisErrorMessages()     # solver error messages
warnings = staad.GetAnalysisWarningMessages()  # solver warning messages

GetAnalysisStatus() raises an exception when the run returned an error (negative) status code — execute_code reports it; no try/except needed unless you want to continue after a failure.

Print Options

P-Delta Analysis

cmd = staad.Command
cmd.PerformPDeltaAnalysisNoConverge(NoOfIterations=5, PrintOption=0)

cmd.PerformPDeltaAnalysisEx(
    NoOfIterations=20, PrintOption=0,
    bSmallDelta=1,            # 1=P-small-delta, 0=P-large-delta
    AddGeometricStiffness=1   # 1=include geometric stiffness
)

Buckling Analysis

cmd.PerformBucklingAnalysis(MaxNoOfIterations=10, PrintOption=0)

cmd.PerformBucklingAnalysisEx(
    Method=0,                # 0=Iterative, 1=Eigen
    MaxNoOfIterations=15, PrintOption=0
)

Cable Analysis

cmd.PerformCableAnalysis(NoOfIterations=25, PrintOption=0)

cmd.PerformCableAnalysisEx(
    AdvancedCableAnalysis=1,
    AdvOptions=[1, 0],   # [REFORM, KGEOM]
    Params=[145, 300, 1e-4, 0.0, 1.0, 1, 0.0],
    PrintOption=0
)

Direct Analysis (AISC)

cmd.PerformDirectAnalysis(
    Option=1,                      # 1=LRFD, 2=ASD
    Params=[0.01, 0.01, 1, 15],    # [TAUTOL, DISPTOL, ITERDIRECT, PDiter]
    AddOptions=[0, 0],             # [REDUCEDEI, TBITER]
    PrintOption=0
)

Nonlinear Analysis

cmd.PerformNonlinearAnalysisEx(
    PrintOption=0, Arclength=0.0,
    NoOfIterations=5, Tolerance=0.0009,
    Steps=10, Rebuild=0,
    AddGeometricStiffness=1,
    DispLimitData=[joint, DOF, target]  # DOF: 1-3=trans, 4-6=rot
)

Floor Diaphragm

cmd.SetFloorDiaphragmBaseCommand(elevation)
cmd.DeleteFloorDiaphragmBaseCommand()

Seismic Check Commands

cmd.SetCheckSoftStoryCommand(DesignCode=3)
cmd.SetCheckIrregularitiesCommand(DesignCode=3)

Delete Commands

cmd.DeleteAllAnalysisCommands()

Steel Design via Command (Low-Level)

cmd.CreateSteelDesignCommand(
    NDesignCode=1067, NCommandNo=9380,
    IntValues=[1], FloatValues=[], StringValues=[],
    NAssignList=[1, 2, 3]
)

For workflows, prefer the staad-steel-design skill which uses the Design sub-module.

Example

See run-analysis.py for a complete working example.

Gotchas

• Do NOT call PerformAnalysis more than once — it adds duplicate commands
• Must call SaveModel before AnalyzeModel — the engine reads from the .std file on disk
• Wrap AnalyzeModel/AnalyzeEx in SetSilentMode(True/False) to prevent blocking dialogs
• For design workflows always use AnalyzeEx(1, 0, 1) — never AnalyzeModel
• AnalyzeEx runs both analysis AND design; AnalyzeModel runs analysis only
• Compression-only springs/supports (elastic mat, plate mat with `springType=1`) are incompatible with P-Delta, Nonlinear, Buckling, and Cable analysis — the engine uses member/spring deactivation iterations that cannot coexist with geometric nonlinearity or those other solver loops. The engine will throw an error. Use plain PerformAnalysis + AnalyzeEx for models with compression-only supports.