STAAD.Pro Model Checking Checklist Before Analysis

STAAD.Pro will analyse an incomplete, unstable, or mis-unit model and still return numbers. Model checking is the work of refusing those numbers until the file represents the intended structure. It is cheaper than arguing about a utilisation ratio that came from a duplicate node at a base.

This checklist is ordered the way errors actually cascade: units and geometry, then properties, then supports and releases, then loads, then a cautious trial run to read warnings. It complements nodes and coordinates, member properties and load cases. It is not a code check and it does not replace output review after a successful run.

Do this before converting to AutoCAD or issuing reactions. Staad2CAD will faithfully export a dirty skeleton. Checking is what makes that export ethical.

Geometry checks that tables catch and renderers hide

Print or review joint coordinates, member incidences, duplicate-node reports, zero-length members and orphan joints. Measure overall width, eave and a bay against the input register. Confirm origin versus architectural grids. If this layer fails, stop. Properties cannot rescue a cracked skeleton.

Connectivity

Portals that only look connected, braces that miss work-points, and supports on the twin of a duplicate node are the greatest hits. Merge with inspection, not with a reckless tolerance.

Dummy members

Load-application beams and drafting aids should be isolated so they cannot take force or export to CAD as steel.

Property, support and release checks

Every member needs a property. Unused properties should not clutter the list. Supports should match the intended pinned, fixed or spring story. Releases should match connection intent. A fully fixed GUI default on a PEB pinned-base job is a system error, not a preference.

Supports

Walk the base joints. Count supports versus columns on the plan. Springs, if used, should be documented so reactions are not read as rigid-base values.

Releases and truss specs

Rod bracing modelled as beam elements without a tension-only or truss spec will carry compression the rods cannot. That error passes a pretty view.

Load-list checks without inventing combinations

Confirm self-weight once, named primary cases, and combinations that match the design basis. Delete leftover combinations from copied files. Prefix trial cases. Details are in the load cases article; the checklist item is: the printed list ticks against the basis. Do not create new factors during checking.

• Self-weight present once.
• Empty cases deleted.
• Direction cases split as needed.
• Combinations named as the basis names them.
• No imported combinations from another jurisdiction.
• Trial cases excluded from issued envelopes.

A trial run is a probe, not an issue

After static checks, run a simple gravity case (if the basis includes one) and look: deflections the right way, vertical reactions roughly consistent with expected weight, no wild spins at a released joint. Then run the issued combinations and still treat the first output as something to review, not to email.

If the trial looks wrong, you just saved the CAD team a week. If it looks right, archive the file name you will convert from. Checking includes deciding which file is the parent of drawings.

Who checks, and what gets written down

A person who did not build the last fifty members should walk the checklist. Record units, axis, support story, and combination source on an analysis cover note that will be issued with drawings. That note is part of checking, not bureaucracy.

1. Checker named; date named.
2. Failed items logged; not silently fixed without a note if they affected issued sketches.
3. File saved as a revision, not as “model” overwritten forever.
4. Permission to convert to CAD only after this checklist is ticked.

Pre-analysis STAAD.Pro check sequence

Order matters. Do not start with steel-design ratios.

1. Units, vertical axis, origin versus grids.
2. Geometry reports: duplicates, orphans, zero-length, overall dimensions.
3. Dummy members isolated.
4. Properties and materials complete; tapers match intent.
5. Supports and releases versus drawings.
6. Load list versus design basis.
7. Trial gravity (or simplest valid case) and warning review.
8. Archive and only then full combinations, output review, and optional CAD convert.

Engineering tips

• Keep a one-page office checklist; this article is the commentary, not a substitute for your QA form.
• If a warning cites a member number, resolve it before deleting the warning from the printout.
• Check braces in a plan view; 3D hides misses.
• Compare column count to support count with a table, not with a glance.
• When copying a bay, re-run duplicate-node reports; copy is a geometry event.
• Do not “check” by enabling steel design and hoping ratios look familiar.

Fake checking

Orbiting the 3D view and calling it QA

You will miss 2 mm gaps, wrong releases and leftover combinations. Use reports.

Clearing instability by adding random supports

You just changed the building. Find the disconnected member instead.

Checking properties on one typical and assuming groups are clean

Specials and copied bays are where wrong sections hide. Read the full table.

Converting to CAD because the deadline hit, then checking later

Drawings will freeze the dirt. Check first, even a shortened checklist, then convert.

STAAD.Pro pre-analysis checklist

Tick on a printed form. Unticked means do not issue.

• Units and vertical axis confirmed.
• Overall dimensions match the freeze.
• Duplicate and orphan joints resolved.
• No zero-length members.
• Dummy members isolated.
• All members have intended properties.
• Supports match base intent and count.
• Releases and truss specs match connection intent.
• Load cases and combinations match the design basis.
• Trial run warnings read and resolved.
• File archived with a revision name.
• Checker named; CAD export not started early.

Frequently asked questions

How much checking is enough on a small portal frame?

The same layers: units, geometry, properties, supports, loads, warnings. A small model fails in the same ways as a large one; it just fails faster. You can walk it in minutes if the file is clean.

The analysis completed — doesn’t that mean the model is OK?

No. Completion means the solver ran. Unintended pins, missing self-weight and wrong combinations all “complete.” Checking is about intent, not about a green finish message.

Should I check again after a small load edit?

Re-tick loads and warnings. If geometry and properties did not change, you may not need a full geometry pass. If you copied members to apply the load, you need geometry again.

Can automation replace this checklist?

Scripts can dump duplicate nodes and empty properties. They cannot tell you whether a pin was intended. Use reports plus a human who has read the drawings. Converters like Staad2CAD do not perform this check.

Checking is the first analysis result

A STAAD.Pro model that has not been checked is a hypothesis. Units, joints, properties, supports, load lists and warnings are the first results you owe the project. Ratios and CAD sheets come after. Skipping the checklist does not save time; it relocates the time to site and to comment cycles.

Use this with output review after the run. Checking does not certify member adequacy or combination correctness beyond matching the stated design basis. That remains the responsible engineer’s work.