Strut-and-tie software, compared
There are only a handful of tools built for strut-and-tie modelling, and they differ more than the category name suggests — some are desktop suites where STM is one module, some are single-purpose web apps, one is a free university tool that stopped being maintained.
This table is the honest version: what each one runs on, what it covers, and what the vendor publishes as its price. Where a vendor does not publish a figure, it says so rather than guessing.
| Software | Runs on | 2D / 3D | Design codes | Published price | Academic |
|---|---|---|---|---|---|
| AStrutTie (Web) | Browser — no install | 2D and 3D | ACI 318, AASHTO LRFD, Eurocode 2, KDS | From $100/month ($1,000/year); perpetual $2,000 (Std) / $3,000 (Pro) | Pro free for 12 months |
| IDEA StatiCa (Detail) | Desktop (Windows) | 2D and 3D | Eurocode, ACI and others | Detail via Complete / Enterprise, approx. €1,750–4,990/year | Student and campus programme |
| GSBT | Browser — no install | 2D | EN 1992-1-1, DMRB CS 455, ACI 318-19 | £210 / 3 months · £360 / 6 months · £650 / 12 months | Free on request from an academic email |
| FRILO BSM+ | Desktop (Windows) | 2D | Eurocode / DIN | Editions from €244/month; module price on request | Not published |
| CAST | Desktop (Windows) | 2D | ACI 318 | Free | Free (research tool) |
| Fachwerk3D | Desktop (Java) | 3D | Not stated | Free (GPL) | Free (GPL) |
Reading the table
Free is not always maintained
CAST and Fachwerk3D cost nothing, and for a class or a one-off check that can be exactly right. Both have gone years without an update — Fachwerk3D is listed at version 0.4.5 with a compatibility warning on modern systems — so treat them as study tools rather than as production software under a deadline.
A module inside a suite is priced like a suite
In IDEA StatiCa and FRILO, strut-and-tie is one module of a larger package. If you use the rest of the package that is good value; if you only need STM, you are paying for the parts you do not open.
Web is not automatically the same thing
GSBT and AStrutTie both run in a browser, and that shared trait hides the real difference: GSBT is 2D with EN, CS 455 and ACI; AStrutTie adds 3D models and AASHTO plus the Korean KDS codes. Pick on the codes and the dimensionality you actually need.
3D is where the field thins out
Most STM tools are planar. If your work is pile caps, three-dimensional pier or abutment models, the shortlist is short — and it is worth checking that a tool's '3D' means a solved spatial truss rather than a 3D view of a planar model.
Which fits your work
Choose AStrutTie if
your work is strut-and-tie specifically, you want 3D as well as 2D, you need AASHTO or KDS alongside ACI and Eurocode, or you want people on any operating system to open the same model without an install.
Choose IDEA StatiCa if
you already run the suite for steel connections and concrete detail, want CSFM stress-field results alongside strut-and-tie, and the suite budget is already approved.
Choose GSBT if
you work to EN 1992 and CS 455 in the UK, your models are planar, and a short subscription of a few months matches how you buy.
Choose CAST or Fachwerk3D if
you are teaching or studying the method, cost must be zero, and an unmaintained tool on an old machine is acceptable.
See what ours actually produces
Rather than take the row above on trust — open a worked example, or read how every result is verified against independent references.
Product names and trademarks belong to their respective owners. This comparison is compiled from each vendor's publicly available information on the date stated; it is not endorsed by those vendors. Where a figure is not published we say so rather than estimating.