ETABS & SAP2000 Agents

Getting Started

The ETABS and SAP2000 agents let you build structural models through conversation. Describe what you want, and the agent creates the model automatically. The agents work through the Stru AI desktop app running on the same computer where ETABS or SAP2000 is installed. The agent controls your local software directly, with your licenses, templates, and files. New to the desktop app? Start with Install & Sign In, then come back here.

Install Stru AI App

Download the Stru AI desktop app and install it on your machine with ETABS or SAP2000 (step-by-step install guide).

Launch the App

Run the Stru AI app on your computer. It connects your local ETABS/SAP2000 installation to the agent.

Sign in with your email. Then use the dropdown in the top-left corner to choose ETABS Agent or SAP2000 Agent for the software you want to drive.

Start the Client

Use the Client control in the top-right corner to connect the app to your local ETABS/SAP2000. A green dot means the client is connected and ready. From the same dropdown you can Restart client (reconnect) or Stop client (disconnect). The Update button keeps the app on the latest version. More detail: Connecting ETABS & SAP2000.

Client controls: Restart client and Stop client

Configure Settings

Open Settings (gear icon, top-right) to verify the app is connected with SAP2000/ETABS and to check/update the working directory. The agent will use this directory to save new models and access existing models.

Chat with the Agent

You can chat with the agent in two ways:Option 1, in the app: Once the client shows a green dot, type your request in the Message the agent… box at the bottom of the app window and start building. Everything runs against your local ETABS/SAP2000.

Option 2, via browser: Go to app.stru.ai, select ETABS Agent or SAP2000 Agent from the top-left dropdown, then click the monitor icon with the green dot to connect to your computer app. Chat from the website while the agent drives your local software.

Build and Save Locally

Models are created in your local ETABS/SAP2000. Save files directly to your machine using the working directory configured in the app settings, use your own templates, and leverage your local computing resources.

Why local? Full control over your files, access to your templates and section databases, fast performance, and everything stays on your machine.

Pro Tip: Use @ to search building codes while writing prompts. Try @ASCE 7 for wind loads or @ACI 318 for concrete design.

Agent in Action

Watch the SAP2000 Agent build a steel structure through the Stru AI desktop app:

The Stru AI app runs on your machine and connects to your local ETABS/SAP2000 installation. You chat through the app or your browser while the agent controls the software directly on your computer. The interface shows:

Center: Interactive 3D model views from SAP2000/ETABS - click to select elements for modification
Right panel: Agent’s explanation of what was built and validation summary
Bottom: Task breakdown with completed (✓) and in-progress (⚡) steps

ETABS vs SAP2000: Which Agent?

ETABS Agent

Choose for:

Buildings (high-rise, concrete frames, shear walls)
Floor diaphragms and vertical load distribution
Building-specific seismic and wind design
Story-based modeling workflows

SAP2000 Agent

Choose for:

Bridges, trusses, space frames
Industrial structures and towers
Long-span systems and stadiums
General-purpose structural analysis

Writing Effective Prompts

The Golden Rule

Either be specific OR explicitly give the agent discretion. Avoid vague prompts.

Create a 4-story building:
- Plan: 120ft x 80ft
- Bays: 4 @ 30ft in X, 4 @ 20ft in Y
- Story heights: 15ft ground, 12ft typical
- Columns: W14x120
- Beams: W21x50
- Units: kip-ft

Create a 4-story office building, roughly 120ft x 80ft.
Use your engineering judgment for bay spacing, member
sizes, and story heights appropriate for office loads.

Create a building with some beams and columns.

Key Prompt Elements

Specify Units Upfront

Always include units in your first prompt:✅ “Use kip-ft units for this model…”Prevents unit confusion later.

Break Complex Tasks

For complex structures, work incrementally:

First, create the basic frame geometry.
[Review screenshot]
Now add X-bracing to perimeter frames.
[Review again]
Finally, apply gravity loads.

Be Clear on Directions

Specify load directions clearly:✅ “Apply loads in gravity direction (downward)”✅ “Wind loads in Global Y direction”✅ “Distributed along member length”

Common Use Cases

ETABS Examples
SAP2000 Examples

Concrete Building Frame

Create a 5-story reinforced concrete frame:
- Plan: 100ft x 75ft
- 5 bays @ 20ft in X, 5 bays @ 15ft in Y
- Story height: 12ft typical
- Columns: 24"x24", Beams: 18"x24"
- Concrete: f'c = 4000 psi
- Apply loads: DL=120psf, LL=60psf

Adding Shear Walls

Add concrete shear walls to the existing frame:
- Walls on gridlines A and D (perimeter)
- Wall thickness: 12"
- Height: Full building height
- Connect to existing frame with rigid connections

Modifying Existing Model

Option 1: Describe the changes

Change all columns on levels 3-5 to 24"x30".
Keep levels 1-2 as 24"x24". Show before/after comparison.

Option 2: Select and modify Click to select specific columns in the 3D viewer, then: “Change these selected columns to 24”x30""

Floor Diaphragm Modeling

Add floor diaphragms at all levels:
- Slab thickness: 8"
- Diaphragm type: Rigid
- Include openings for stairs and elevator shafts
- Apply floor loads: DL=120psf, LL=60psf

Steel Truss Bridge

Create a 100ft Warren truss:
- Span: 100ft, Depth: 12ft, Panel spacing: 10ft
- Top chord: HSS10x10x5/8
- Bottom chord: HSS8x8x1/2
- Web members: HSS6x6x3/8
- Supports: Pin at left, roller at right

Space Frame Structure

Create a 60ft x 60ft space frame roof:
- Grid: 10ft x 10ft spacing
- Height: 15ft at center, 10ft at edges (sloped)
- Members: HSS4x4x1/4 for all elements
- Support: Columns at perimeter grid points

Steel Frame with Bracing

Create a 3-story industrial steel frame:
- Plan: 80ft x 60ft, 4 bays @ 20ft, 3 bays @ 20ft
- Story heights: 20ft ground, 15ft typical
- Columns: W14x90, Beams: W18x35
- Add X-bracing on gridlines A and D, all stories
- Use HSS8x8x1/2 for braces

Load Combinations

Apply gravity loads to all beams:
- Dead: 1.2 kip/ft (includes self-weight)
- Live: 0.8 kip/ft
- Wind: 40 psf lateral pressure

Create ASCE 7-22 load combinations for gravity and wind design.

Advanced Usage

Study and Recreate Existing Models

The agent can analyze existing models and recreate them with modifications:

Open 'Existing_Building.sdb' and study its geometry, sections,
and loads. Then create a similar model but with:
- 20% taller story heights
- Updated to ASCE 7-22 wind loads
- Member sizes optimized for new loads

Use cases: Modernize old models to new code provisions, create design variations, or standardize legacy projects.

Compare Two Models

Compare different design options:

Compare 'Option_A.sdb' and 'Option_B.sdb':
Total steel weight difference
Drift ratios under lateral loads
Foundation reactions comparison
Cost implications of member size differences

Use cases: Design optimization, value engineering studies, structural system selection, and code compliance verification.

Use Sketches and Floor Plans

Upload drawings to convey information:

I'm attaching a floor plan sketch. Create a 3-story model
based on this layout. Use W14 columns and W18 beams.
Story height: 12ft.

What you can upload: Hand-drawn sketches, PDF floor plans, marked-up elevations, or structural diagrams. The agent interprets dimensions, grid layouts, and structural intent from images.

Parametric Design and Iterations

Rapidly generate design variations for optimization studies, value engineering, and sensitivity analysis.

ETABS Parametric Studies
SAP2000 Parametric Studies

Lateral system comparison

Model the same building with three lateral systems:
1. Perimeter moment frames
2. Interior braced frames
3. Concrete shear walls at core

Compare drift, period, material quantities, and foundation demands.

Floor system optimization

Create 4 variations of floor framing:
1. Post-tensioned slab (8" thick)
2. Two-way concrete slab (10" thick)
3. One-way joist system (24" depth)
4. Composite steel deck (3" deck + 12" beams)

Compare cost, weight, and floor-to-floor height.

Building height study

Create iterations for 4, 6, 8, and 10 story variations:
- Keep same footprint (120ft x 80ft)
- Adjust column sizes for increased height
- Compare seismic base shear and drift
- Report steel/concrete quantities per floor

Truss depth optimization

Create 3 models with truss depths of 10ft, 12ft, and 15ft:
- Same 120ft span
- Keep all other parameters constant
- Report: Deflections, steel weight, connection complexity

Bridge cable configuration

Model cable-stayed bridge with different cable patterns:
1. Fan arrangement (all cables from tower top)
2. Harp arrangement (parallel cables)
3. Semi-fan hybrid

Compare deck moments, tower forces, and cable quantities.

Member size optimization

Create 5 design iterations:
Base case: Space frame with HSS4x4x1/4
Iterations:
1. HSS5x5x5/16 (heavier)
2. HSS3x3x3/16 (lighter)
3. Mixed sizing (perimeter vs interior)
4. Optimize for minimum weight under deflection limit

Save each and compare weight/deflection tradeoffs.

The agent handles the repetitive modeling work, letting you focus on engineering decisions.

Best Practices

Starting New Model
Modifying Models
Load Application

Always specify units firstInclude units in your opening prompt: “Create a model using kip-ft units…”Build geometry before loadsCreate structure first → Review screenshot → Apply loads → Verify patterns → Run analysisSave incrementallySave at major milestones: “Save as ‘Building_BaseFrame_v1.sdb’ before we modify the lateral system”

Troubleshooting

Model Doesn’t Look Right

Request Multiple Views

Show me:
- Isometric view
- Plan view at level 2
- Elevation along gridline A

Check Geometry Details

List all frame members with their coordinates and sections.

Start Fresh if Needed

This isn't quite right. Let's create a new model.
This time, use 4 bays @ 25ft instead of 5 bays @ 20ft.

Agent Seems Stuck

If the agent stops responding, keeps repeating the same step, or gets caught in a loop, work through the fixes below from top to bottom: start with a prompt nudge, and only restart the client or model if prompts don’t help.

Recovery ladder: (1) Ask for status → (2) Redirect with a prompt → (3) Simplify or break it down → (4) Start the task from scratch → (5) Restart the client → (6) Close the model and start a fresh session. Each step is a bigger reset than the last.

Try a Prompt First

Ask for Status

See where the agent is before changing anything:

What's the current status? Which step are you on, and
are you stuck or waiting on something?

Ask It to Rethink the Approach

Nudge the agent to step back instead of pushing the same path:

This approach doesn't seem to be working. Stop and
rethink it. Explain a simpler plan before you make any
more changes, then proceed once the plan looks right.

Simplify the Request

Strip the task down to the essentials and add detail later:

Let's pause. Just create the basic frame geometry
without loads for now.

Break It Down

Instead of one complex prompt, use a sequence and review between steps:

Create geometry
Add lateral system
Apply loads
Run analysis

Start the Task From Scratch

If the model is in a bad state, have the agent abandon it and rebuild cleanly:

Let's start over from scratch. Discard the current
progress, create a new model, and rebuild it step by
step. Confirm each step with a screenshot before moving on.

Reset the Session If prompts aren’t getting through, the connection between the app and ETABS/SAP2000 may have hung. Reset it.

Restart the Client

Open the Client dropdown in the top-right of the app and choose Restart client. This reconnects the app to ETABS/SAP2000 without closing your model. Wait for the green dot, then send your prompt again.

Close the Model and Start Again

If a restart doesn’t help, the ETABS/SAP2000 model itself may be in a stuck state:

Stop client from the Client dropdown.
Close the model in ETABS/SAP2000 (save first if you want to keep it).
Reopen ETABS/SAP2000, then Restart client and wait for the green dot.
Ask the agent to reopen your saved model, or start a fresh build.

A clean model and a fresh client connection clears the large majority of stuck states.

Still Stuck?

If the agent is still stuck after a full restart, click Update (top-right) to make sure you’re on the latest app version, then try again. If the problem persists, email support@stru.ai with a short description and a screenshot.

Loads Not Applied Correctly

Verify Load Patterns

List all load patterns and show which members have
loads in the DEAD case.

Check Direction

Verify the loads are applied downward (gravity).
Reapply if the direction is wrong.

Visualize

Screenshot with load arrows visible.

Real-World Workflow

Complete design sessions showing iteration and refinement:

ETABS: Office Building
SAP2000: Truss Bridge

Initial Model

Create a 4-story office building:
- 150ft x 100ft plan
- 5 bays @ 30ft in long direction
- 4 bays @ 25ft in short direction
- Story heights: 15ft ground, 13ft typical
- Use engineering judgment for member sizes
- Units: kip-ft

Agent creates model with W14x176 columns, W24x62 beams

Optimize

Beams seem heavy. Try W21x50 for levels 2-4,
keep W24x62 at ground only.

Agent updates sections

Add Lateral System

Make perimeter frames on gridlines A and E moment-connected
for lateral resistance.

Agent modifies connections

Apply Loads

Floor loads:
- Dead: 100psf (slab + MEP + ceiling)
- Live: 50psf (office)
- Roof: Dead 80psf, Live 20psf

Create ASCE 7 gravity combinations.

Agent applies loads and combinations

Verify

Before analysis, show:
Isometric with loads visible
Total applied loads by level
List of load combinations

Agent provides verification package

Save

Save as 'Office_Gravity_Rev1.edb'

Agent saves and provides download link

Initial Model

Create a 150ft Pratt truss bridge:
- Span: 150ft, Depth: 20ft
- Panel spacing: 15ft (10 panels)
- Top chord: HSS12x12x5/8
- Bottom chord: HSS10x10x1/2
- Verticals/diagonals: HSS8x8x3/8
- Units: kip-ft

Agent creates truss geometry with member assignments

Add Deck System

Add bridge deck:
- Width: 30ft
- Composite steel girders @ 10ft spacing
- Connect deck to top chord at panel points

Agent adds deck framing

Refine Supports

The bearing at the right end needs to allow thermal
expansion. Change it to a guided roller support allowing
movement in the longitudinal direction only.

Agent modifies boundary conditions

Apply Bridge Loads

Apply loads:
- Dead: Deck self-weight + 25 psf utilities
- HL-93 live load pattern on deck
- Wind: 30 psf lateral on exposed area

Create AASHTO load combinations.

Agent applies bridge loading

Check Member Utilization

Show me a summary of member forces and highlight any
members with high stress ratios. Focus on diagonals and
chord members.

Agent provides force summary with critical members flagged

Save

Save as 'Truss_Bridge_Rev1.sdb'

Agent saves and provides download link

Tips for Success

Iterate freely - Don’t expect perfection first try. Refine with follow-ups: “Can you adjust the bay spacing to be more uniform?”
Interactive selection - Click elements in the 3D viewer to select them, then ask the agent to modify your selection
Request screenshots - Ask for visual verification at key stages: “Show isometric view to confirm bracing layout”
Upload references - Attach floor plans, sketches, or existing models to guide the agent and convey complex information visually
Compare options - Generate multiple design variations quickly for value engineering and optimization studies

Next Steps

Set Up the Desktop App

Install the Stru AI app and pair it with your account.

Connect Your Software

The Client pill, working folders, and detected versions.

Upload a Sketch

Create a model from a floor plan or structural drawing.

Reference Codes with @

Tag ASCE 7, ACI 318, AISC 360, and IBC in your prompts.

Questions? Email support@stru.ai or book a call to discuss your use case.

Agent Guides

How-To Guides

Desktop App

API Reference

ETABS & SAP2000 Agents

Getting Started

Agent in Action

ETABS vs SAP2000: Which Agent?

ETABS Agent

SAP2000 Agent

Writing Effective Prompts

The Golden Rule

Key Prompt Elements

Common Use Cases

Concrete Building Frame

Adding Shear Walls

Modifying Existing Model

Floor Diaphragm Modeling

Steel Truss Bridge

Space Frame Structure

Steel Frame with Bracing

Load Combinations

Advanced Usage

Study and Recreate Existing Models

Compare Two Models

Use Sketches and Floor Plans

Parametric Design and Iterations

Best Practices

Troubleshooting

Model Doesn’t Look Right

Agent Seems Stuck

Loads Not Applied Correctly

Real-World Workflow

Tips for Success

Next Steps

Set Up the Desktop App

Connect Your Software

Upload a Sketch

Reference Codes with @

​Getting Started

​Agent in Action

​ETABS vs SAP2000: Which Agent?

ETABS Agent

SAP2000 Agent

​Writing Effective Prompts

​The Golden Rule

​Key Prompt Elements

​Common Use Cases

​Concrete Building Frame

​Adding Shear Walls

​Modifying Existing Model

​Floor Diaphragm Modeling

​Steel Truss Bridge

​Space Frame Structure

​Steel Frame with Bracing

​Load Combinations

​Advanced Usage

​Study and Recreate Existing Models

​Compare Two Models

​Use Sketches and Floor Plans

​Parametric Design and Iterations

​Best Practices

​Troubleshooting

​Model Doesn’t Look Right

​Agent Seems Stuck

​Loads Not Applied Correctly

​Real-World Workflow

​Tips for Success

​Next Steps

Set Up the Desktop App

Connect Your Software

Upload a Sketch

Reference Codes with @

Getting Started

Agent in Action

ETABS vs SAP2000: Which Agent?

Writing Effective Prompts

The Golden Rule

Key Prompt Elements

Common Use Cases

Concrete Building Frame

Adding Shear Walls

Modifying Existing Model

Floor Diaphragm Modeling

Steel Truss Bridge

Space Frame Structure

Steel Frame with Bracing

Load Combinations

Advanced Usage

Study and Recreate Existing Models

Compare Two Models

Use Sketches and Floor Plans

Parametric Design and Iterations

Best Practices

Troubleshooting

Model Doesn’t Look Right

Agent Seems Stuck

Loads Not Applied Correctly

Real-World Workflow

Tips for Success

Next Steps