01 — DRAW
Members by hand
Drag to place each member. Shared ends weld into a node automatically; endpoints snap to the grid.
The workflow
Draw it. Load it. Solve it.
Three moves take you from a blank canvas to a fully solved structure — no menus, no set-up, no desktop software.
02 — LOAD
Supports & loads
Drop pins, rollers and fixed supports onto nodes. Add point, moment and distributed loads onto members.
03 — SOLVE
Read the behaviour
One tap solves every connected structure. Scrub any member for exact reactions, shear, bending and deflection.
Live in your browser
Solve a beam, right here.
This is the same engineering the app runs in one tap — a real solver, computed live as you drag. Move the load, switch the diagram, and watch the structure respond.
Drag the red load on the beam · pick a diagram below
Interactive beam
Simply supported · pin + roller · 6.0 m span
How it works
From a blank canvas to a solved structure
The same four steps the in-app walkthrough teaches — designed so the theory behaves the way you expect.
1
Draw
Drag to place members. Members that share an end automatically join at a node, and endpoints snap to the grid and to existing nodes. Tap any length to type an exact value.
2
Support & load
Drop pins, rollers and fully-fixed supports onto nodes. Add point loads, moments and distributed loads — uniform or trapezoidal — onto members. A drop ring turns green the moment it will attach.
3
Analyse
Tap Analyse. Each connected structure in the workspace is solved on its own with the direct stiffness method — stable ones are solved, unstable mechanisms are detected and clearly flagged.
4
Read
Toggle reactions, shear, bending, axial and the deflected shape. Scrub along any member to read the exact value at any point — critical values are located for you automatically.
Features
Built like real structural analysis — only friendlier
Every part of the app maps to how a real beam or frame is drawn, loaded and solved.
Draw by hand
Place each member with a drag
Members that share an end weld into a node automatically, endpoints snap to the grid and to existing nodes, and you can tap any length to type an exact value. Two fingers pan and zoom — or turn on Apple Pencil mode to draw while your fingers navigate.
- Auto-join shared ends into nodes
- Grid & node snapping
- Apple Pencil draw mode
Real supports & honest loads
Supports and loads that match reality
Pin, roller and fully-fixed supports — tap to set the orientation, then drag onto a node. Point loads, moments, and distributed loads that can be uniform or trapezoidal with separate start and end magnitudes, acting perpendicular to the member or locked to a global axis.
- Pin, roller & fixed supports
- Uniform or trapezoidal distributed loads
- Per-member material & section properties
A genuine solver
Solved with the direct stiffness method
Every structure is solved with the same direct stiffness method used in professional analysis software. Build several independent structures in one workspace and each is solved on its own; unstable structures and mechanisms are detected and clearly highlighted.
- Multiple structures, each solved independently
- Mechanism & instability detection
- Switch N / kN and mm / m units
Results you can interrogate
Every governing value, at a glance
Toggle reactions, shear, bending, axial and the deflected shape. Scrub along any member to read the exact value at any point, tap a single reaction to inspect it alone, and let the app locate the critical values for you. Show, blur or hide the loads and supports over the diagrams.
- Scrub for exact values anywhere on a member
- Automatic critical-value location
- Tap a single reaction to inspect it
Read the results
Five diagrams. One language.
iStruct2D speaks the same colour language an engineer reads on paper — so every diagram is instantly legible.
R
Reactions
Support forces resolved at every restraint — tap one to inspect it alone.
V
Shear
The internal shear force stepping along the member.
M
Bending
The bending-moment diagram, with maxima found for you.
δ
Deflection
The deflected shape, exaggerated so you can see how it moves.
Axial force is drawn in red — tension and compression read at a glance across a truss.
Inside the app
A workspace that gets out of your way
Real screens from iStruct2D running on iPad.
Who it's for
See the theory behave
Students
Learning statics and structural mechanics — watch reactions, diagrams and deflected shapes behave exactly as the theory predicts.
Educators
Demonstrating reactions, internal forces and deflected shapes live in class — sketch a structure and solve it in front of the room.
Engineers
Sketching a quick check or sanity-testing a result on the go — from the back of a napkin to a solved frame, on your iPad.
Co-developed with UQ
The University of Queensland, School of Civil Engineering
Direct stiffness method
The same solver foundation as professional software
On-device & private
Projects stay on your iPad — no account, no tracking
Your iPad, your structural sketchpad.
Draw a beam, frame or truss with your finger, add supports and loads, and tap once for reactions, shear, bending, axial and deflection. Now in beta.
iStruct2D is in beta and intended for learning, exploration and preliminary reference. Results are for reference only and must be independently verified — always apply your own engineering judgement. iStruct2D is not a substitute for a qualified structural engineer, accredited design software, or compliance with any building code or standard.