Terms & Conditions

Data Security

We are committed to ensuring that your information is secure. In order to prevent unauthorised access or disclosure we have put in place suitable physical, electronic and managerial procedures to safeguard and secure the information we collect.

All data is stored in secure electronic systems accessible only to Oasys staff with both valid network login credentials and specific authorisation to access the system.  Our systems further limit data access by role to ensure data is available only to those who have a specific need to see it.

If at any point you suspect or receive a suspicious communication from someone suggesting they work for Oasys or a website claiming to be affiliated with Oasys, please forward the communication to us or report the incident by email to [email protected] or in writing to Oasys, 8 Fitzroy Street, London, UK, W1T 4BJ as soon as possible.

Data Security Notice Updated 27th February 2020

top ]


Website Terms and Conditions

The contents of this web site are protected by copyright and other intellectual property rights under international conventions. No copying of any words, images, graphic representations or other information contained in this web site is permitted without the prior written permission of the webmaster for this site.

Oasys accepts no responsibility for the content of any external site that links to or from this site.

top ]



Software Licensing Terms

Terms and Conditions of Purchase

The full conditions of purchase and maintenance for all Oasys desktop software are set out in the Oasys Software Licence and Support Agreement.

The full conditions of purchase and maintenance for Oasys Gofer and Oasys Giraphe are set out in the Gofer SaaS Agreement  and the Giraphe SaaS agreement.

All prices are subject to TAX at the current rate.

Prices and specifications are subject to change without notice – please ask for a written quotation.

Although every care has been taken to ensure the accuracy of all information contained herein, the contents do not form or constitute a representation, warranty, or part of any contract.

Superseded Versions of Terms and Conditions

Oasys keeps copies of all superseded versions of its terms and conditions.

Maintenance & Support Services

Support and maintenance is included with all subscription licences for their full duration.

Annual maintenance contracts are available for software under a perpetual licence, prices are based on a percentage of the most recent list price.

This service includes:


top ]



Cookies Policies

View available cookies policies below:


top ]


Sydney’s beautiful double helix bridge at Lachlan’s Line

Software Used on this Project

Project Overview

The digital engineering-led approach to the project from concept to completion of this unique ‘double helix’ bridge in Sydney, Australia, has delivered a successful structure that has really hit the sweet spot between form and function. Is it a piece of art in the city, or is it a beautiful showcase of engineering? Why not both? The bedrock of the design process was robust structural analysis by Oasys GSA, used in conjunction with a range of software tools, all BIM compatible and readily interoperable. It enabled engineers to evolve a more fluid shape and to overcome site-specific space constraints and geotechnical challenges.


As well as sheer beauty, the irregular helical geometry met the practical requirements to safely connect two areas previously separated by a junction. This allowed the regeneration of a brownfield site plus a whole new city district to be brought to life. The distinctive blue bridge now provides safe and easy pedestrian and cyclist access to the city rail network for residents of the new Lachlan’s Line urban village. You can read more about the Arup-led project here.

The striking 178m long structure is believed to be the first of its kind in the world. Basically, the helix is a tubular truss and the deck sits inside without doing any spanning work.  The truss dimensions follow structural demand, so it is deeper over the supports where the bending moments of the beam are higher and shallower at mid span where the moments are lower. In this GSA-optimised design, the diameter of the truss varies from 5.5m to 7.8m.


How Oasys proved invaluable

Oasys GSA used in conjunction with Rhino and Grasshopper is a powerful combination that enabled a parametric design approach. Engineers specified the key parameters of the project and made changes interactively, with the model updating automatically. No longer the preserve of architectural visualisation, parametric design is increasingly embraced by good engineers to amplify their core skills, make more efficient designs, explore more options, and optimise buildings.

The project team made good use of compatibility between GSA and Rhino, to model and explore the possibilities of the unique shape of the bridge, and Grasshopper to build generative algorithms and undertake the parametric design. Geometry Gym plug-ins further eased the seamless, bespoke workflow. It was a powerful and synergistic toolbox that meant that changes to the permanent design could be quickly analysed at the design stage, as well as being queried when the structure was in temporary states during lifting and positioning.

More than 3,600 unique steel plates were required but with all the design programs and models linked together, a single modification – at any stage of the workflow – adjusted every subsequent model instantly, updating in minutes, not weeks. It also updated Revit documentation and saved BIM models that contained all the steel data. Innovation was continuous throughout the design process.

This level of automation meant that the team had more time and opportunity to focus on sustainability by minimising material usage and simplifying the construction process.  For example, the plate thickness of each side of the fabricated box sections is optimised, minimising the amount of steel needed.


Oasys GSA is the benchmark for structural analysis and is scalable and affordable for schemes of any size. Armed with this and the assurance of the software interoperability demonstrated on this project, engineers will continue to enjoy increasing freedom to explore new ideas like the Lachlan’s Line Bridge.

Special thanks to Alexandra Bogdanova for the beautiful images.

What is your query?

  • This field is for validation purposes and should be left unchanged.

Newsletter Sign up

Please fill out your details below to receive the latest oasys news.

  • This field is for validation purposes and should be left unchanged.