Automatic geometry & mesh
The full bridge layout - arches, ties, hangers, cross beams and wind bracing - generated from numerical inputs, with a 1D mesh you never have to police.
Now available - free version, released 2026
Tied-arch bridge pre-design, in minutes.
BowstringPRO turns a handful of geometric and loading parameters into a complete 3D model, load cases, combinations and Eurocode verifications for steel tied-arch and network arch bridges - so you can compare concepts before you commit to one. Developed by ArcelorMittal and CCES.
Free of charge · Windows desktop · Software + user manual in one package · Developed by CCES with ArcelorMittal
3Bridge wizards: road, rail, footbridge
7National Annexes implemented
5Hanger arrangements, incl. network
ULS·SLS·FLSVerifications to the Eurocodes
Developed by
How it works
Three steps between an idea and a checked concept
No node-by-node modelling, no manual lane placement, no hand-built combination matrix. You define the parameters that actually distinguish one concept from another - BowstringPRO builds the rest.
Enter the parameters
Span, width, rise, hanger arrangement, bracing, cross sections, traffic and loading data - entered through a road, rail or footbridge wizard with schematic guidance at every field.
The model builds itself
A 3D linear model with an automatically generated 1D mesh, plus every load case and Eurocode combination the configuration requires. Nothing to check for stray nodes or misplaced elements.
Analyse, verify, report
The built-in FEM solver runs static, modal, spectral and buckling analyses. Section and member design checks follow, and summary or detailed reports export straight to .docx.
Capabilities
A proprietary solver behind a deliberately simple interface
Everything the pre-design phase needs for a technical and economic comparison - and nothing that slows it down.
Automatic loads & combinations
Permanent, live and traffic load cases with Eurocode combinations built for you. Lane placement and moving loads take a few inputs rather than a few days.
Proprietary FEM solver
Linear 1st-order static analysis, modal analysis by subspace iteration, spectral dynamic analysis and linear buckling (stability) analysis - all in one package, no external solver required.
ArcelorMittal section database
Geometric properties drawn directly from ArcelorMittal's profile databases - including HISTAR® grades - alongside user-defined sections.
High-speed rail dynamics
Spectral dynamic analysis under high-speed train models, with displacements, accelerations and rotations reported per train, per speed and per mass configuration.
Reports in .docx
Summary and detailed reports covering geometry, sections, loads, reactions, internal forces, stresses, deflections, fatigue and stability - ready to drop into a tender submission.
Multilingual, SI or custom units
Independent language selection for the interface and for the generated reports, plus a unit system you can adapt to the conventions of the project.
Design checks with capacity ratios
Every structural element returned with its least favourable ratio and the combination or envelope that produced it, so weak points surface immediately.
Aeroelastic hanger checks
Vortex shedding, galloping and rain–wind-induced oscillation checks for solid bar and flat hanger sections, following EN 1993-2.
Scope
Three wizards, one structural family
Tied-arch bridges with a deck simply supported on foundations. The deck and arches are designed by the software; foundations are outside its scope, with support reactions provided for the foundation designer.
Road bridges
Load Models 1 to 4, exceptional LM3 convoys, tramway loads, lane configuration, footways, surfacing and drainage layers - all through the road wizard.
Rail bridges
Load Models 71, SW/0 and SW/2, plus dynamic analysis under HSLM high-speed train passage with deck displacements, accelerations and rotations per train and speed.
Footbridges
Uniformly distributed and concentrated pedestrian loads, service vehicle and accidental loads, with deflection control - for the lighter spans where arch geometry is the whole design argument.
Geometry
Five hanger arrangements, including true network arches
Switch arrangement, change the number of hangers, adjust the inclination - and re-run. Comparing a vertical arrangement against a network solution becomes an afternoon, not a project phase.
VerticalType A
RadialType B
Fan-shapeType C
Bowstring trussType D
NetworkType E
Arches may be vertical or inclined, with or without wind bracing in X, K, I or IK configurations - and the bridge may be skewed.
Compliance
Built on the Eurocodes, annex by annex
Actions, design and verification follow Eurocodes 0, 1, 3, 4 and 8 for bridges - with the national choices that actually decide a tender.
- Ultimate limit state - tension, compression, bending, shear, torsion and their interactions, with automatic section classification to EN 1993-1-1.
- Serviceability limit state - deflection control for road, pedestrian and railway decks, horizontal arch deformation and stress control.
- Fatigue limit state - stress ranges and cycle counts per element against the defined fatigue load models.
- Stability & buckling - linear buckling eigenmodes with critical load factors and a buckling check per selected mode.
- Toughness - maximum permissible material thickness reported for every structural element.
- Seismic - modal analysis by subspace iteration and generation of seismic loads to Eurocode 8.
Eurocodes applied
- EN 1990
- EN 1991
- EN 1993
- EN 1994
- EN 1998
National Annexes implemented
- Germany
- France
- Poland
- Italy
- Luxembourg
- Belgium
- United Kingdom
Inside the software
A workspace built for comparison, not for modelling
The interface is deliberately narrow. Three wizards describe the bridge, one command runs the analysis, and the result windows report every element against the combination that governs it. There is no model to assemble and no load matrix to maintain, so the time goes into comparing concepts rather than building them - change a hanger arrangement or a section family, re-run, and read the new ratios.
Editions
Start free today. Expert Mode is on its way.
The free version covers the full pre-design workflow with hot-rolled sections for the arches and the intermediate cross beams. Expert Mode opens up welded and user-defined plate sections and every remaining option.
Available now
Free version
Free of charge · software + user manual in one download
- Road, rail and footbridge wizards
- All five hanger arrangements, including network
- Hot-rolled sections from the ArcelorMittal database
- Full ULS, SLS, fatigue, stability and toughness checks
- Modal, seismic and high-speed rail dynamic analysis
- Summary and detailed .docx reports
Next release
Expert Mode
Everything in the free version, plus the full option set
- Welded plate arch sections
- Welded plate cross-beam sections
- Custom and user-defined built-up sections throughout
- Every remaining modelling option unlocked
Download
Get BowstringPRO
The package contains the software and the full user manual & technical reference. A Windows desktop application, free of charge, for professional users active in steel construction.
The collaboration
Bridge engineering expertise, steel expertise, one tool
BowstringPRO was developed through the collaboration of a specialist structural software team and ArcelorMittal's research and engineering organisations.
Conception Consulting Engineering Solutions
Structural engineering and software development. Author of the analysis engine, design checks and user interface.
ArcelorMittal Global R&D and Steligence® Engineering
Research direction, section data and validation of the Eurocode implementation against current steel practice - together with application engineering and support for designers using ArcelorMittal products in bridge structures.