Workspace setup
Your workspace key links this page to the StructAuto Connector on the PC that runs ETABS.
Workspace key
Put the same key in the connector. Anyone with this key can run jobs on that PC's ETABS and see its results, so keep it private.
Connector
No key set.
The connector is a small program on the PC with ETABS that lets this page run ETABS there. Not installed yet? See Connector download. It works with ETABS 21; ETABS 22 and later are not supported yet.
Project settings file
Keep a copy of your project's inputs and settings in one file. Open it later, or on another PC, to carry on where you left off. The StructAuto desktop app opens the same file (File → Load Settings…).
AI assistant (your own Claude API key)
Optional. With your own Anthropic API key, StructAuto can check your inputs before a build and answer questions about your results. The AI runs on your Anthropic account and is billed there. Get a key at console.anthropic.com (API keys).
Your key stays in this browser and is sent only to Anthropic (api.anthropic.com), never to the StructAuto server. Unticked, it is forgotten when you close the tab. Summaries of your inputs and results are sent to Anthropic under your account's terms. AI answers can be wrong: you remain responsible for the design, and code clause numbers it quotes should be checked against the code text.
Connector download
The StructAuto Connector lets this web page run ETABS on your PC. Install it on the PC that has ETABS.
StructAuto Connector for Windows
No Python needed, no administrator rights needed.
- Run StructAuto_Connector_Setup.exe. If Windows SmartScreen warns, click More info → Run anyway.
- Start StructAuto Connector from the Start menu or the desktop.
- On first start it asks for your workspace key. On Setup click Copy next to your key, paste it and click Check and save.
- Keep the connector window open while you work. The status at the top right turns Connector online.
Requirements
- Windows 10 or 11, 64-bit
- ETABS 21 installed with a valid licence (tested with ETABS 21.2)
- Internet connection while you work
Good to know
- Change the key: Start menu → StructAuto Connector → Change workspace key.
- Stop: close the connector window. Let a running job finish first; stopping in the middle can leave ETABS unstable.
- Update: download and run the new installer over the old one. Your key is kept.
- Uninstall: Windows Settings → Apps → StructAuto Connector.
- Use the connector on one PC per key. Need it on a second PC? Ask the owner for another key.
Modeling
Grid, stories, sections and plan layout, with the same inputs as the desktop app's Modeling tab. Entries are kept in this browser.
Grid and general
The code preset sets the design code, material and default loads. Seismic hazard values come from the preset; set them in ETABS, as in the desktop app.
Stories
| Story | Height | Elevation at top |
|---|
Sections
Sizes are rounded to multiples of 5 cm (2 in for imperial units) when the model is built, the same as the desktop Sections dialog.
Columns start at the ground-story size and get smaller going up, never below the smallest size. An unticked taper box keeps that dimension at its ground-story size on every story; untick both for constant columns. The same largest and smallest sizes are the limits for the Optimization engine and the RS design cycle.
How the size reduces going up
Example: reduced by 5 cm every story gives width 65 → 60 → 55 cm and height 70 → 65 → 60 cm from the ground story up.
Changes the sizes in the current model instead of building a new one. Members on sections you made yourself in ETABS are left alone.
Plan layout
Open an existing ETABS model
Use this instead of building when you already have an .edbLoading
Load patterns and values that the Build job creates in ETABS together with the model.
Load patterns and material
Seismic hazard values come from the code preset in Modeling. Set them in ETABS, as in the desktop app.
Filled in by the code preset. Must match a material name ETABS knows.
Dead loads
Wall line loads go only on the beams you mark in Modeling → Plan layout, Wall loads mode. Open the plan editor
Live loads
Live wall line loads also go only on the beams marked in the plan editor (live or both).
Analysis
Acts on the model open in ETABS: no model reported yet. Open a different model
Run analysis
Runs the analysis and exports results (all cases and combinations) to Excel next to the model. Story drift, torsion ratio, base reactions and modal results appear below when it finishes.
Model info
Reads the open model's file name, ETABS version, load patterns, cases and combinations. Also fills the lists under Get results.
Get results
Run Model info first to fill the case lists.
Response spectrum analysis
Reset these settingsWhich spectrum goes with which design code
| Spectrum | Design code | Seismic design combinations | Minimum Vdyn/Vstatic |
|---|---|---|---|
| ASCE 7-16 | ACI 318-19 (US) | 1.2D + 0.2SDSD + 1.0L ± E, 0.9D − 0.2SDSD ± E (ETABS's own) | 1.0 (§12.9.1.4.1) |
| Eurocode 8 | Eurocode 2-2004 (EU) | G + ψ2Q ± E (EN 1990 §6.4.3.4, ETABS's own), + 30% other direction | none required by EC8 |
| TBDY 2018 | TS 500-2000 R2018 (TR) | (1 + 0.2SDS)G + Q ± E, (0.9 − 0.2SDS)G ± E, + 30% (Eq. 4.11/4.12, written by StructAuto) | enter TBDY's value (check §4.8) |
| User defined | the code your spectrum comes from | as for that code | as for that code |
Filled from the model's seismic settings. ETABS computes Fa, Fv, SDS, SD1 (§11.4); the case scale factor is g·Ie/R. Drift is also shown × Cd/Ie.
Cases, modes and checks
ASCE 7-16 §12.9.1.4.1 requires the full static base shear (ratio 1.0), filled in when ASCE is picked. Enter your code's ratio for others. Damping is 5% and the direction combination SRSS (ETABS defaults). Leave a static case blank to skip the comparison.
ACI and Eurocode: each seismic design combination (e.g. 1.0 G + 0.3 Q ± EQX for Eurocode, 1.3 Dead + 1.0 Live ± EQX for ACI/ASCE) is copied with the RS case instead, keeping its factors (RS results are already ± envelopes). TS 500: StructAuto writes the TBDY 2018 ones, (1 + 0.2 SDS) G + Q + E1 + 0.3 E2 and (0.9 − 0.2 SDS) G + E1 + 0.3 E2 (Eq. 4.10–4.12). Regenerate when the code family changes, so gravity and wind combinations follow the code too. Tick scaling first so the RS forces meet the minimum base shear. Then run Concrete design with the same code.
RS design cycle
Analysis, scaling and design repeated until the sections settle. Each cycle: the response spectrum analysis above (RSX/RSY scaled to the minimum ratio, RS design combinations), then the Optimization engine with its own settings, which designs with those combinations and resizes members. Resizing changes the periods, both base shears and the scale factor, so a cycle that changed any section is followed by another. From cycle 2 the engine only grows members, so the sizes can't drift down cycle after cycle. It stops when a cycle changes no section (or at most 2% of the frames while the scale factors move under 2%), then re-runs the response spectrum analysis and scaling with the final sizes and runs a final concrete design.
Needs Scale ticked and a design combinations option. Tick Include beams on the Optimization page to let it grow failing beams (e.g. shear + torsion). Can take many minutes: each cycle is two analyses plus every engine iteration. Stop it from the Jobs panel.
Concrete design
Runs ETABS concrete frame design on the open model (no model reported yet). The model must already be analysed.
Design code
Leave blank to use the model's current design code, or pick a preset to switch codes before designing.
Which design codes your ETABS includes is shown here once the connector is online.
Results list errors, warnings and the governing column PMM ratio. Choose which station tables to save in _Design.xlsx next to the model.
Optimization engine
Resizes columns (and beams, if chosen) in place on the model open in ETABS, without a rebuild. Column size limits and the taper step come from Modeling → Sections. Settings are kept in this browser.
Iteration and column steel ratio targets
A column needing more steel than the max ratio grows one step; one needing the min ratio or less shrinks.
Columns
Blank = off
Blank or 0 = no cap
How column resizing and rotation work
Column size limits (max/min width and height) and the minimum taper step come from Modeling → Sections. Beams have their own limits on the Beams tab. With a fixed thickness, each column's smaller side is held at that value and only its long side changes. Directional torsion turns a column so its long side faces the weak direction (already facing it: the long side grows one step). With the drift check on, when drift is over the limit in one direction and the other direction has room, up to a quarter of the column lines per iteration turn to face it: on the side that pulls the rigidity center toward the mass center, or symmetrically from the perimeter, never pushing the other direction past 85% of its limit. A column always has the same orientation on every story (never crossed between floors): the whole column turns together.
Story drift and torsional irregularity
Needs ETABS' "Calculate Diaphragm Centers of Rigidity" (Analyze > Set Load Cases to Run) and an analysis since. Otherwise it falls back to symmetric, non-targeted column growth.
Beams
Every span of a continuous line (collinear beams sharing joints; a missing bay starts a new line) gets the largest size any of its spans needs, so a frame is never 30×50 / 30×60 / 30×50. No span becomes smaller than its own need. "On every story" also makes the same line equal from story to story (fewer beam types, more concrete).
Reinforcement detailing
Turns the designed steel areas into buildable bar layouts. Reads from ETABS only and never resizes sections. PMM verification needs one run of this stage.
Bar selection
Applies to columns and beams.
Columns
Beams
Top and bottom steel are detailed separately, using only the bar selection settings. Continuity, symmetry and max ratio apply to columns only.
Column standardization
Optional, reporting onlyReporting only: the result appears in the reinforcement output and report.
PMM verification
Check-mode compliance of the columns against the target PMM ratio range. Run once after Reinforcement detailing.
Rebar material and target PMM ratio range
Must already exist as a Rebar-type material in ETABS (Define > Material Properties). This stage cannot create one.
Below the low value a column counts as under-utilized (over-designed); above the high value it fails the target.
Auto-correction
Off: only the rebar is reduced (never below the minimum column steel ratio above) and only overstressed columns grow, so the sizes chosen for drift and torsion are kept. On: underutilized columns can also get smaller, but drift and torsion are not re-checked, so run Analysis and check them afterwards.
Auto-correct does not re-check drift or torsion and covers columns only. Each iteration runs 2 full ETABS analyze + design passes. It also uses the Reinforcement settings and the Optimization engine's size increment, taper, max size jump and rename settings.
Reports
The desktop File menu's reports. Excel and HTML files are saved next to the model on your PC. Detailed job result JSON is saved locally in Documents/StructAuto_Results.
Full structural report
Uses the last Run analysis, plus Run design and Reinforcement detailing if they ran, all since the connector started.
Reinforcement report
Bar layouts from the last Reinforcement detailing run, with column standardization if it was computed.
PMM verification report
Compliance, rebar assignment and correction history from the last PMM verification run.
Users and access
Only you (the owner's Google account) can see this page. Approving a sign-up emails that user; revoking stops their web page and connector within 30 seconds.
Users
Temporary full-result viewing is off by default. Enable Allow temporary web details only for selected users; their requested cloud copy expires after 24 hours.
| Name | Email / company | Reason | Registered | Connector | Status | |
|---|---|---|---|---|---|---|
| Loading… | ||||||
Your admin workspace
Not listed under Users: it is always active and can't be revoked by mistake. Use this key in your own connector.
…
Connector release (update offer)
When you publish a newer version here, every connector of version 1.1.0 or later asks its user at its next start (or within a day) whether to install it. Nothing installs without the user's Yes, and a download whose fingerprint doesn't match is refused.
One email per user per version: version, what's new and how to update. Google lets this app send about 100 emails a day (5 are kept for sign-up codes); if more users are waiting, use the button above on another day. Nobody gets the same version twice.
Steps for a new version: build the connector (it prints the version and SHA-256), upload StructAuto_Connector_Setup.exe, paste the link and fingerprint here, then Publish. The Download button on the Connector download page uses this same link, so new users get the same version.
Access period
How long a user's access lasts after you approve them. When it ends, their page and connector stop working and they have to register again with a new email address (the old one can't be used again). Your own workspace never expires.
Applies to users you approve from now on. Users already approved keep their end date; extend them below.
Days are added to the current end date, or to today if the access has already ended. An expired user works again as soon as you extend them.
Daily job limit
The project-wide cap counts every job submitted by non-owner accounts, including helper jobs. At the warning threshold, StructAuto emails the owner; at the cap, new submissions pause until midnight (Cyprus/Turkey time). The default cap is 500 jobs per day. This app-level limit helps control activity but does not set a Firebase billing budget. Your own workspace is exempt.
To turn on the bot check, create a score-based reCAPTCHA Enterprise key for mystructauto.com, register it for this web app in Firebase Console → App Check, and grant the Functions runtime service account the Firebase App Check Token Verifier role. Paste the public site key above and save. Until then, the email, IP and site-wide request limits remain active.
Connector check-in interval
How often a waiting connector asks the server for new jobs. Fast while someone has the web page open (in view, or used in the last 10 minutes); slower otherwise, which spares the server when PCs are left running. Applies to every workspace within one check-in.
Shorter means jobs start sooner but the server is busier. A job submitted after a quiet spell waits at most one "not in use" interval. Running jobs are not affected.