Getting started with Struxt3D

Struxt3D is a structural analysis and design app that runs entirely in your web browser. There is nothing to install and no account to create: open the app and start a model. This chapter takes you from an empty page to a designed structure, then explains where your work is kept.

#What you need

• A current desktop browser — Chrome, Edge, Firefox or Safari. The 3D view uses WebGL and the solver runs as WebAssembly in a background worker, so the page stays responsive while it computes.
• A mouse or trackpad. The app works on tablets and phones, but drawing and reading tables is easier on a larger screen.
• Storage allowed for the site. Struxt3D keeps your current model in the browser's local storage. In a private window, or with site data blocked, it still works, but the model is gone when you close the tab unless you save it to a file.

#Your first model in five minutes

This walk-through uses the multi-storey frame, but every template follows the same four steps.

1. Open the app. Go to /app/. The first screen asks What are you building? and shows the template gallery. Hover a card to preview the structure in 3D behind the gallery.
2. Pick a template. Click Multi-storey frame. The model is built with its default sizes and you move to the Size step.
3. Set the size. Change spans, bays and storeys with the − and + buttons, or type a value. The model rebuilds as you go, and the chips under the view show its overall dimensions and how many members, columns, beams and supports it has. Click Next: materials.
4. Choose the code and material. Pick a design code (for example Eurocode or AISC / ACI), then Steel, Concrete or Timber, a grade, and the section of each member group. Leave Size members for me on and Struxt3D will pick the lightest sections that pass. Click Next: supports & loads.
5. Set supports and loads. Choose fixed or pinned bases, the floor use (office, residential, retail, storage), finishes, and switch wind or earthquake on or off. Self-weight and the code's load combinations are added for you.
6. Run the analysis. Click Run analysis (or press F5). In a few seconds you are in the workspace with the deflected shape and forces on the model.
7. Run the design. Click Run design in the results panel (or press F6). Every member is checked to your code, members are sized, and the model is coloured by utilization: anything over 1.00 shows in red.

From here, click a member to see its section, utilization and governing check, open the calculation report, or change something and run again.

#Opening a template from a tutorial

Each structure tutorial on this site has an Open the template button. It opens the app with that template already chosen and its default sizes set, so you land directly on the Size step. The link has the form /app/?template=<id>, for example /app/?template=portal-frame-shed. Once the template is open, the address bar goes back to plain /app/, so reloading the page keeps your changes instead of starting the template again.

#Where your work is kept

#Automatic saving in the browser

Every change you make is saved to your browser's local storage a moment later. When you come back to /app/ on the same computer and browser, the gallery shows a Continue “…” button with your project's name. Click it to return to the workspace where you left off.

Only one project is kept this way — the one you worked on last. Starting a new template replaces it once you make a change. Clearing your browser's site data removes it.

#Saving to a file

To keep a project for good, share it, or work on several, save it as a file:

• Simple interface: the save button in the top bar (Save the project (.s3d)).
• Full interface: File › Save or the save button on the toolbar.
• Anywhere: Ctrl+S.

The file downloads with the project's name and the .s3d extension. Open it again with the open button, File › Open…, Ctrl+O, or the Open a project link at the foot of the template gallery. More on this in Saving, opening and exporting.

#What next

• The interface: Simple and Full — a tour of the workspace.
• Choosing a template — the 21 structures and drawing your own.
• How structural analysis works — the engineering behind the numbers.