Manual

Getting started

Open the editor and you get a blank canvas with a toolbar on the left and a Properties panel on the right. Pick a tool, click on the canvas to place something, then select it to change how it looks. Nothing is installed, and nothing is saved until you ask for it.

The editor is built for a mouse and keyboard, so it needs a desktop or a laptop. Phones and tablets are not supported yet.

Moving around the canvas

What object snap catches

Every tool

Tools are grouped by how many clicks they need. Press Escape at any point to cancel what you are drawing. Looking for one in particular? Use the search box.

Selecting and editing

Click an element with the Select tool to select it. Its settings appear in the Properties panel on the right.

Double-click an element to show its blue handles, then drag a handle to reshape it. Double-clicking a text label or a callout opens it for typing instead.

Drag a selected element to move it. Hold Shift while dragging to keep it on one axis.

Hold Ctrl (Cmd on a Mac) and drag to copy instead of move: the original stays where it is, faded, while the copy follows the cursor. Add Shift to keep the copy on one axis. It works on a single element or a whole selection, and a copied group becomes a group of its own.

To select several at once, use Box Select, or hold Ctrl (Cmd on a Mac) and click each one. Ctrl+A selects everything.

Nudge a selection with the arrow keys, one pixel at a time, or hold Shift for a full grid square.

If elements overlap, click the same spot again to step down through them.

Right-click a selection for Group, Ungroup, Save as Template, Bring to Front and Send to Back. Grouped elements move together, and have to be ungrouped before you can resize them individually.

The Rotate tool turns a selection around a pivot. Hold Shift, or turn Ortho on, to snap the rotation to 15° steps.

Changing how things look

Everything in the Properties panel applies to the one selected element; with several selected, it shows only how many. To change what a tool draws next time, select the tool with nothing else selected, set it up there and click Save as Default. Save as Default with an element selected does the same for that element’s type, using its style.

Exporting a diagram

Exporting is part of a Membership.

1. 1

   Open Export. The Export button is in the top bar.

2. 2

   Choose a format. PNG for a plain image, or SVG to keep the diagram sharp at any size.

3. 3

   Set the options. Turn on a transparent background, and pick a resolution for PNG.

4. 4

   Select the area. Click Start Snipping, then click two corners around the part of the canvas you want.

5. 5

   Download. Check the preview, then download. Select again if the crop is not right.

Projects and templates

Saving projects and templates both need a Membership.

A project is a whole diagram saved to the cloud. Save it from the top bar, and reopen it from any computer by signing in. You can keep up to 20.

A template is a piece you want to reuse. Select the elements, right-click and choose Save as Template. Templates follow your account, so they are there on any computer you sign in on. You can keep up to 100; delete one to make room for another.

If a Membership lapses, saved projects stay in place and can still be opened, and templates you already saved can still be placed on the canvas. Either can be deleted; saving new ones and renaming are paused until it is renewed.

Keyboard shortcuts

Getting started

Open Structural analysis from the top navigation and sign in with Google. The first time, a notice explains what the tool does and what its results are for; tick the box to continue. It asks again only if the notice changes.

A first visit opens on a worked example — a two-span beam with dead, live and wind load cases — so there is something to read before anything is drawn. File › New model gives an empty one, and File › Start from an example brings back the continuous beam, a truss or a portal frame.

The model on screen is kept in this browser under your account, so closing the tab does not lose it. Like the editor, the tool needs a desktop or laptop.

Drawing the structure

Everything is on the Structure menu and on the toolbar under it. There is no beam or truss mode: whatever is drawn is what gets solved, and a member hinged at both ends is a truss member.

Loads, cases and combinations

Running the analysis

The Analyse list on the bar over the drawing picks what is solved: every case, one on its own, or a set chosen in the Analysis window. Press Calculate, F5 or Ctrl+Enter.

Before solving, the model is checked: a member with no length, a joint with nothing holding it, a joint lying on a member it is not joined to, a load past the end of its member. Anything that stops the analysis is listed with a way to find it, and clicking an item selects what it is about.

After solving, every result checks itself: the structure is in equilibrium, the solution satisfies its own equations, and every joint balances. A result that fails is shown with a warning not to use it, and no report can be printed from it.

A free account analyses models of up to 15 members. Larger models and load combinations need a Membership, and the window that says so offers it.

Reading the results

The report

Report (Ctrl+P) gathers the drawing and the tables onto one sheet, sized for A4, A3, Letter or Legal, to print or save as PDF from the browser.

A free account prints a one-page summary of one load case: the drawing, the reactions and the largest and smallest axial force, shear, moment and deflection in the structure, each with where it occurs, plus the first step of the calculation as a sample. A light “FREE PLAN” watermark runs across every page.

With a Membership the report covers every case and combination, the input as well as the results, the calculation worked step by step — stiffness matrices, assembly, solution and recovery — carries no watermark, and saves as Word.

Every report carries the line “For education and preliminary checking only — verify independently before use.” at the top and at the foot of each printed page.

Keeping models

The model on screen is always kept in this browser, under the account that drew it.

File › Open, Save and Save as keep models in your account, to open again from any machine — up to 100 of them. That is part of Membership; after a Membership ends, what was saved can still be opened and deleted.

Units and grid

Keyboard shortcuts

What it does not do

This tool analyses 2D structures by the direct stiffness method — linear elastic, small displacements. It does not check buckling, second-order effects or any design code. Results depend on the model you enter and may contain errors, from the model or from the software. They are for education and preliminary checking only and must be independently verified by a qualified engineer before use in design, construction or any decision affecting safety.

How the program is checked against textbook solutions is on the verification page, and the method is written out in full in the direct stiffness method guides.