Civil

Structural

SAP2000

ETABS

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Process automation in structural engineering, driven by programming languages such as Python, is growing exponentially due to its ability to minimize errors, reduce time, and optimize results. 

SAP2000 is a finite element software by CSI (Computers & Structures, Inc), used for modeling, structural analysis, seismic-resistant design and dimensioning of structures in civil engineering projects, ranging from bridges and buildings to stadiums and dams. It allows for detailed and accurate simulations. 

While SAP2000 offers a wide range of features, it can take time to perform the initial setup, modeling and extraction of results. To address this, its API allows repetitive tasks to be automated, reducing the likelihood of user error and increasing work efficiency. 

Through the API, several tasks can be automated, including: 

- **Templates:** Define commonly used structural elements. 

- **Preprocessors:** Automate load applications and configurations. 

- **Postprocessors:** Create custom algorithms for project verifications. 

- **Parametric Models:** Script-based model creation and modification. 

- **Custom Plugins:** Develop tools to add functionality to SAP2000. 


## Data Exchange: Bi-directional connections with Revit and other tools. 

CSI's API is currently available for SAP2000, ETABS and CSiBridge, it has been developed to be as consistent as possible between the various CSI products, allowing any tool and/or application to be easily adapted between products. 

In this blog we will provide tutorials to learn how to automate data entry and extraction with the SAP2000 API. 

Let's get started! 

To start you should have Python installed and then configured Visual Studio Code (VS Code).

**Install necessary libraries** 

To properly follow this blog series, you’ll need to install the comtypes, numpy, pandas, and matplotlib libraries. 

You can install numpy by running “pip install numpy” at the command prompt or in the terminal. Similarly, you can install pandas by running “pip install pandas” and comtypes by running “pip install comtypes==1.1.14”.

 
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## SAP2000 API Documentation 

The SAP2000 API documentation provides the information necessary to use its functions and methods. It includes detailed descriptions of the functions, their parameters and usage examples. 

API documentation is available within the CSI_OAPI_Documentation.chm Windows help file, located in the SAP2000 installation directory. 

*“C:\Program Files\Computers and Structures\SAP2000 24\CSI_OAPI_Documentation.chm”* 

![Imagen1.png](https://cms.viktor.ai/uploads/Imagen1_ab95add901.png)

Every action we perform in the SAP2000 software interface, such as creating a new concrete material, defining a rectangular section, assigning a distributed load to a Frame element, running the model, reading tables, and more, can be performed using Python code. 

**Example Code** 

To start using the API functions the documentation provides an example with Python where a structure is modeled, properties are defined and the analysis is executed to extract the results. To see the code used we must follow the following path in the documentation:  

*Example Code -> Example 7 (Python COM)*

![Imagen2.png](https://cms.viktor.ai/uploads/Imagen2_f3207a2c33.png)

[Here is the example Python file from the documentation](https://drive.google.com/file/d/1IcBCvUueyiHqYmo5ayYBDFFk1bjB9z1C/view?usp=sharing)

You will have to run the code in VS Code and wait... 

![blog-sap2000-1-6.png](https://cms.viktor.ai/uploads/blog_sap2000_1_6_2698c6f1e1.png)

The code will automatically open SAP2000, initialize a new blank model, create a concrete material, define a rectangular Frame section, set up the units, draw the Frame elements, apply node constraints, create load patterns, assign point and distributed loads, save the model, run the analysis, extract the results from the nodes, and finally close the program. 

![image 979.png](https://cms.viktor.ai/uploads/image_979_fe94a95847.png)
![image (17).png](https://cms.viktor.ai/uploads/image_17_45ad84b928.png)


**Let's break down the sample code!** 

The first 60 lines of the example code in the documentation will allow us to open the latest version of the SAP2000 program that we have installed. But I share with you a more summarized version of that code to open SAP2000 with Python: 

```import os
import sys
import comtypes.client

# create API helper object
helper = comtypes.client.CreateObject('SAP2000v1.Helper')
helper = helper.QueryInterface(comtypes.gen.SAP2000v1.cHelper)

# create an instance of the SAPObject from the latest installed SAP2000
mySapObject = helper.CreateObjectProgID("CSI.SAP2000.API.SapObject")

# start SAP2000 application
mySapObject.ApplicationStart()

# create SapModel object
SapModel = mySapObject.SapModel
```

A new model is started using the **New Blank Template, with the option to select other templates such as 'NewGridOnly' or 'Steel Deck'. 

```# initialize model
SapModel.InitializeNewModel()

# create new blank model
ret = SapModel.File.NewBlank()
```

The properties of a new reinforced concrete material called *“CONC”* are defined using the **SetMaterial** method of the **PropMaterial** property of the SapModel object **(SapModel.PropMaterial.SetMaterial)**, according to the documentation the enumeration for the material type Concrete is 2 and for the reinforcing steel is 6.  

To define the mechanical properties and set the symmetry as isotropic, we use the **SetMPIsotropic** method **(SapModel.PropMaterial.SetMaterial)**, the documentation indicates the parameters to enter. 

```# define material property
MATERIAL_CONCRETE = 2
ret = SapModel.PropMaterial.SetMaterial('CONC', MATERIAL_CONCRETE)

# assign isotropic mechanical properties to material
ret = SapModel.PropMaterial.SetMPIsotropic('CONC', 3600, 0.2, 0.0000055)
```
![blog-sap2000-1-9.png](https://cms.viktor.ai/uploads/blog_sap2000_1_9_48896eac86.png)

To create a rectangular section we use the **SetRectangle** method of the **PropFrame** property of the SapModel object **(SapModel.PropFrame.SetRectangle)**. The section will be called *'R1'* and will be associated with the previously defined *'CONC'* material. Its dimensions will be 12 inches by 12 inches. In addition, for defining section property modifiers, the SetModifiers method is used. It is crucial to use the API documentation to understand the necessary parameters.  

```# define rectangular frame section property
ret = SapModel.PropFrame.SetRectangle('R1', 'CONC', 12, 12)

# define frame section property modifiers
ModValue = [1000, 0, 0, 1, 1, 1, 1, 1]
ret = SapModel.PropFrame.SetModifiers('R1', ModValue)
```
![blog-sap2000-1-2.png](https://cms.viktor.ai/uploads/blog_sap2000_1_2_b0e383700e.png)

Note that when defining the mechanical properties of the material and the geometry of the section. By default, we are working in kip, inches, and degrees Fahrenheit." 

To change the unit system, use the **SetPresentUnits** method. This is critical if you need your input/output data in specific units. The documentation lists the enumeration for each type of combination of force, length and temperature units. 

```# switch to k-ft units
kip_ft_F = 4
ret = SapModel.SetPresentUnits(kip_ft_F)
```
![blog-sap2000-1-10.png](https://cms.viktor.ai/uploads/blog_sap2000_1_10_4e3efcf2a8.png)

With the **AddByCoord** method of **FrameObj (SapModel.FrameObj.AddByCoord)** the Frame elements defined by their start and end coordinates will be drawn, and the “R1” section created earlier is assigned to them. To know the necessary parameters, we must use the API documentation. Where the parameters *Name, UserName* and *CSys* are options or default parameters. 
```# add frame object by coordinates
FrameName1 = ''
FrameName2 = ''
FrameName3 = ''
[FrameName1, ret] = SapModel.FrameObj.AddByCoord(0, 0, 0, 0, 0, 10, FrameName1, 'R1', '1', 'Global')
[FrameName2, ret] = SapModel.FrameObj.AddByCoord(0, 0, 10, 8, 0, 16, FrameName2, 'R1', '2', 'Global')
[FrameName3, ret] = SapModel.FrameObj.AddByCoord(-4, 0, 10, 0, 0, 10, FrameName3, 'R1', '3', 'Global')
```
![blog-sap2000-1-21.png](https://cms.viktor.ai/uploads/blog_sap2000_1_21_08c69b38a0.png)

To assign restrictions to a node we use the **SetRestraint** method of **PointObj (SapModel.PointObj.SetRestraint)** but for this we will need to obtain the UniqueName of the Frame node to which we will assign the restrictions, for this we will use the **GetPoints** method of **FrameObj (SapModel.FrameObj.GetPoints).** 
```# assign point object restraint at base
PointName1 = ''
PointName2 = ''
Restraint = [True, True, True, True, False, False]
[PointName1, PointName2, ret] = SapModel.FrameObj.GetPoints(FrameName1, PointName1, PointName2)
ret = SapModel.PointObj.SetRestraint(PointName1, Restraint)

# assign point object restraint at top
Restraint = [True, True, False, False, False, False]
[PointName1, PointName2, ret] = SapModel.FrameObj.GetPoints(FrameName2, PointName1, PointName2)
ret = SapModel.PointObj.SetRestraint(PointName2, Restraint)
```
![blog-sap2000-1-13.png](https://cms.viktor.ai/uploads/blog_sap2000_1_13_31dc4bfc13.png)

To add load patterns the **Add** method of **LoadPatterns** is used. Each load pattern is defined by a name and a load type. Consulting the documentation is essential to understand the enumeration of load types. 

```# add load patterns
LTYPE_OTHER = 8
ret = SapModel.LoadPatterns.Add('1', LTYPE_OTHER, 1, True)
ret = SapModel.LoadPatterns.Add('2', LTYPE_OTHER, 0, True)
ret = SapModel.LoadPatterns.Add('3', LTYPE_OTHER, 0, True)
ret = SapModel.LoadPatterns.Add('4', LTYPE_OTHER, 0, True)
ret = SapModel.LoadPatterns.Add('5', LTYPE_OTHER, 0, True)
ret = SapModel.LoadPatterns.Add('6', LTYPE_OTHER, 0, True)
ret = SapModel.LoadPatterns.Add('7', LTYPE_OTHER, 0, True)
```
![blog-sap2000-1-3.png](https://cms.viktor.ai/uploads/blog_sap2000_1_3_aeda9c8203.png)

To assign forces to a node, we first obtain the UniqueName of the node through the GetPoints method of **FrameObj**. Then, we use the **SetLoadForce** method of **PointObj** to assign a point load to one of the ends of the frame. Distributed loads are applied through the **SetLoadDistributed** method of **FrameObj**. Here, the documentation will guide you to understand the parameters that define the magnitudes of the loads and the directions in which they are applied. 

```# assign loading for load pattern 2
[PointName1, PointName2, ret] = SapModel.FrameObj.GetPoints(FrameName3, PointName1, PointName2)
PointLoadValue = [0, 0, -10, 0, 0, 0]
ret = SapModel.PointObj.SetLoadForce(PointName1, '2', PointLoadValue)
ret = SapModel.FrameObj.SetLoadDistributed(FrameName3, '2', 1, 10, 0, 1, 1.8, 1.8)

# assign loading for load pattern 3
[PointName1, PointName2, ret] = SapModel.FrameObj.GetPoints(FrameName3, PointName1, PointName2)
PointLoadValue = [0, 0, -17.2, 0, -54.4, 0]
ret = SapModel.PointObj.SetLoadForce(PointName2, '3', PointLoadValue)

# assign loading for load pattern 4
ret = SapModel.FrameObj.SetLoadDistributed(FrameName2, '4', 1, 11, 0, 1, 2, 2)

# assign loading for load pattern 5
ret = SapModel.FrameObj.SetLoadDistributed(FrameName1, '5', 1, 2, 0, 1, 2, 2, 'Local')
ret = SapModel.FrameObj.SetLoadDistributed(FrameName2, '5', 1, 2, 0, 1, -2, -2, 'Local')

# assign loading for load pattern 6
ret = SapModel.FrameObj.SetLoadDistributed(FrameName1, '6', 1, 2, 0, 1, 0.9984, 0.3744, 'Local')
ret = SapModel.FrameObj.SetLoadDistributed(FrameName2, '6', 1, 2, 0, 1, -0.3744, 0, 'Local')

# assign loading for load pattern 7
ret = SapModel.FrameObj.SetLoadPoint(FrameName2, '7', 1, 2, 0.5, -15, 'Local')
```
![blog-sap2000-1-16.png](https://cms.viktor.ai/uploads/blog_sap2000_1_16_66ddbf6d15.png)

![blog-sap2000-1-11.png](https://cms.viktor.ai/uploads/blog_sap2000_1_11_d96305aa09.png)

After saving the model using the **File.Save** method, specify the file path with the *ModelPath* variable. 

```# full path to the model
# set it to the desired path of your model
APIPath = 'C:\\CSiAPIexample'
os.makedirs(APIPath, exist_ok=True)
ModelPath = APIPath + os.sep + 'API_1-001.sdb'

# save model
ret = SapModel.File.Save(ModelPath)
```

To run the model analysis the **Analyze.RunAnalysis** method is used.  

```
# run model (this will create the analysis model)
ret = SapModel.Analyze.RunAnalysis()
```

And your model is ready! 

## What's next? 

Using Python is a game changer in structural engineering. If you master the skills to automate your work with Python, you stand out from the crowd. Rather than dealing with repetitive tasks, Python allows you to spend more time creating innovative solutions. 

With VIKTOR, you can turn your Python automations into intuitive and sharable web apps that further streamline your workflow, boost your team's efficiency, and enable you to deliver optimal solutions within no-time.  

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SAP2000 and Python.png

Discover how to use the SAP2000 API to automate processes and optimize project efficiency with Python.

How to use Python to automate SAP2000 

Geotechnical

Mechanical

Environmental

Water

Electrical

Energy

Sustainability

With the new ETABS integration in the VIKTOR platform, any engineer can automate ETABS workflows in minutes, without writing or maintaining code. In this blog, we’ll show you how with three practical examples: comparing structural layouts under gravity loads, evaluating seismic performance, and estimating preliminary footing sizes for a steel warehouse.

The VIKTOR AI platform gives you one place to automate engineering workflows, test these thoroughly and share them with your colleagues. It's built on three pillars that work together, shown below: a knowledge base that gets smarter with every project, governed distribution once an app is ready to scale, and connections into the engineering tools your team already relies on, like ETABS. 

![VIKTOR AI Platform.png](https://cms.viktor.ai/uploads/VIKTOR_AI_Platform_f75d88c5aa.png)

</br>

VIKTOR uses AI to turn a simple prompt into an automated workflow, while VIKTOR Desktop connects that workflow to ETABS running on your computer. No custom coding or complex installations are needed. The connection stays within VIKTOR’s security and access controls, and you can share the app with the right users, review revisions, collect feedback, and improve it without sending scripts around the office. The ETABS integration is currently in its early stages, so it offers the clearest value today for creating new, compact models for feasibility studies, early design testing, and small buildings. 

In this blog, you will automate the following ETABS workflows: 
- A parametric gravity-load building: to compare structural grids and estimate starting sizes for main beams, secondary beams or joists, and columns, saving time on repeated model setup 
- A preliminary seismic braced building: to compare story drift, column demand, and brace axial forces, so you can focus further work on the most promising concept 
- A steel warehouse with roof trusses: save time on early foundation estimates by applying roof gravity loads, calculating support reactions, and sizing preliminary isolated footings 

These three apps were built using just one part of the VIKTOR platform: **the App Builder**. From there, VIKTOR also gives you the tools to **securely share and manage your apps across your organization** and **connect them to the engineering software your team already uses.**

## How do I create a parametric gravity-load building in ETABS with AI? 

The first automation creates a regular reinforced-concrete building with primary beams, secondary beams, and columns. It is a good starting point because it follows a practical early-design sequence. You define a grid, assign gravity loads, run a linear analysis, and review member demands and reactions. You can change the bay layout, number of stories, section sizes, secondary-beam spacing, and dead and live loads without rebuilding the model by hand. The result is not a final code design, but it gives you a reusable basis for comparing layouts and selecting reasonable starting sections for the main beams, secondary beams or joists, and columns. 

 

You can use the prompt box below to open the App Builder and create the first automation. 


Create a parametric 3D reinforced-concrete gravity-frame building

You can download and install [VIKTOR Desktop](https://docs.viktor.ai/docs/create-apps/software-integrations/viktor-desktop/), sign in, and add the ETABS integration. This gives the app a managed connection to the licensed ETABS installation on your Windows machine. 

Once VIKTOR Desktop is online, you can start with a small regular model and let the ETABS integration create a new analysis model from the app inputs. You can use the app to vary the grid, sections, and gravity loads, compare alternatives faster, and check the geometry, load directions, units, and result equilibrium. 

<div style="padding:75% 0 0 0;position:relative;"><iframe src="https://player.vimeo.com/video/1217254325?badge=0&amp;autopause=0&amp;player_id=0&amp;app_id=58479" frameborder="0" allow="autoplay; fullscreen; picture-in-picture; clipboard-write; encrypted-media; web-share" referrerpolicy="strict-origin-when-cross-origin" style="position:absolute;top:0;left:0;width:100%;height:100%;" title="Parametric 3D reinforcerd-concrete gravity-frame building"></iframe></div><script src="https://player.vimeo.com/api/player.js"></script>

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## How do I check seismic drift and bracing forces in ETABS with AI? 


After the gravity example, the focus moves to lateral behavior with a regular steel braced building. This automation is useful for early seismic studies because you can change the number of stories, bay widths, column and brace sections, bracing arrangement, and a user-defined preliminary base-shear coefficient, then compare drift and force demand without rebuilding every alternative. The app returns story displacement and drift, base reactions, column forces, and brace axial forces so you can see which parts of the lateral system control the concept. 

Use the following prompt to create the seismic model and review story drift and bracing forces. 

Check seismic drift and bracing forces in ETABS

After the App Builder creates the app, you can run a compact test model first and compare the ETABS base shear, drift pattern, brace-force signs, and reactions with hand calculations. From there, you can use the App Builder to improve the layout, add result filters, or change the bracing options. This helps you compare alternatives faster while keeping the engineering assumptions visible. 

<div style="padding:56.25% 0 0 0;position:relative;"><iframe src="https://player.vimeo.com/video/1217254324?badge=0&amp;autopause=0&amp;player_id=0&amp;app_id=58479" frameborder="0" allow="autoplay; fullscreen; picture-in-picture; clipboard-write; encrypted-media; web-share" referrerpolicy="strict-origin-when-cross-origin" style="position:absolute;top:0;left:0;width:100%;height:100%;" title="Check seismic drift and bracing forces in ETABS"></iframe></div><script src="https://player.vimeo.com/api/player.js"></script>

</br>

## How do I size warehouse footings in ETABS with AI?

Finally, you can use the same approach to create a steel warehouse with triangular roof trusses. The app lets you control the building span, length, frame spacing, eave height, roof slope, and structural sections. It applies dead and live loads to the roof, runs the ETABS analysis, and uses the governing compressive reaction at each support to estimate an isolated footing size. This connects the warehouse geometry, gravity load path, support reactions, and preliminary foundations in one workflow, so you can compare configurations without rebuilding the model and footing calculations by hand. 

Use the following prompt to create the warehouse model and calculate preliminary footing sizes. 

Size warehouse footings in ETABS

After the App Builder creates the app, you can test it by starting with a small warehouse and comparing the applied roof gravity load with the total vertical reactions. You can then change the span, frame spacing, roof slope, or truss sections and review how each option affects the support reactions and preliminary footing dimensions. This gives you a faster way to compare warehouse configurations and prepare early foundation estimates from the same ETABS model. 

<div style="padding:56.25% 0 0 0;position:relative;"><iframe src="https://player.vimeo.com/video/1217254327?badge=0&amp;autopause=0&amp;player_id=0&amp;app_id=58479%2Fembed" allow="autoplay; fullscreen; picture-in-picture" allowfullscreen="" frameborder="0" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></div>

## How to use AI for ETABS building design 

You have now used three prompts to create ETABS apps for gravity analysis, seismic studies, and warehouse footing estimates. The next question is how you can keep using AI to build and improve these workflows safely. The VIKTOR platform gives you a controlled environment where you can turn more engineering ideas into ETABS applications, test them with small models, and improve them before sharing them with your team. 

The App Builder generates the application code in the VIKTOR platform, and the ETABS integration connects the app to ETABS through VIKTOR Desktop. You do not need to install Python or run AI-generated Python code directly on your computer. The generated code does not receive unrestricted access to your local device. This gives teams a safer way to scale prompt-driven development across the organization, spark innovation, and optimize engineering processes. 

### How does AI know how to create models in ETABS

In addition to providing a safer way to create ETABS apps with AI, the VIKTOR platform includes a knowledge base. The knowledge base is one of the main pillars of the platform. It stores engineering information specific to the industry and your company, including internal methods, design guidance, terminology, and workflow requirements, of course only within your company’s secure environment. AI can combine this knowledge with your prompt and curated ETABS integration guides to create models and applications in ETABS. 


### What's next for the ETABS integration 

The current ETABS integration is optimized for preliminary design workflows that create new models and run supported analyses. The team is now working to extend it with the following capabilities. 
- Direct access to the built-in ETABS cross-section libraries or material database 
- Connections to an ETABS instance that is already running 
- Workflows that use existing models and their results 
- The option to return a saved ETABS model file to the VIKTOR app for download or reuse 

We know these capabilities are central to day-to-day structural engineering. You can help us prioritize them by sharing your use case on the [VIKTOR Community](https://community.viktor.ai/). 

## Conclusion 

These three prompts show how you can use the ETABS integration for gravity analysis, preliminary seismic studies, and warehouse footing estimates without rebuilding every model from scratch. The VIKTOR platform brings the inputs, ETABS analysis, and results into reusable apps that you can test, share, and improve as your workflow develops. This helps you compare concepts faster, keep assumptions visible, and spend less time repeating model setup and result processing. 

Try one of the prompts above and adapt it to an ETABS workflow your team repeats often. You can [start with VIKTOR here](https://www.viktor.ai/sign-up). 

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Learn how to automate ETABS workflows with AI. Build apps for gravity analysis, seismic studies, and warehouse footing estimates without coding.

VIKTOR Blog

Automate ETABS processes with VIKTOR using AI: 3 prompts for preliminary building analysis

How to use Python to automate SAP2000

VIKTOR Blog

Automate ETABS processes with VIKTOR using AI: 3 prompts for preliminary building analysis

How to use Python to automate SAP2000

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