Streamlining bridge construction with BrIM

BIM (Building Information Modelling) has become a widely used tool in the construction industry, which is helping to enhance planning and project management, while ensuring projects are delivered on time and on budget. However, its use in bridge construction has been limited, with its sibling BrIM (Bridge Information Modelling) becoming more commonly used to provide a complete representation of the physical and functional characteristics of a bridge asset, offering an information resource for its entire lifecycle.

Here, Stuart Campbell, Business Development Manager, Engineering at Trimble discusses the six ways BrIM can help bridge construction projects succeed.

Efficient and fast design

Though BrIM improves the whole design-build-operate process, designers reap the benefits first; they can capture the structure and alignment of the road, railway and terrain, and all input, such as geomodels, scanned images and point clouds, can be compiled and used for designing in a way that wouldn’t be possible with physical drawings.

A true BrIM solution is also parametric. Parametric design is based on defining parameters, or in other words, data inputs that are connected with modelled objects. For example, when one parameter is adjusted, such as changing the number of columns on a bridge deck, all of the model objects affected by that change are automatically updated.

In practice, parametric BrIM allows structural engineers to easily and visually create data input schema using an algorithm-based editor and then output objects to a parametric BrIM tool, such as Tekla Structures. Structural engineers are leveraging this workflow without prior knowledge of programming through direct links between BrIM software and visual programming tools such as Grasshopper, which is a pre-installed plugin for Rhinoceros 6, a 3D computer graphics and computer-aided design (CAD) application. This is especially beneficial for creating complex shapes like curved structures and architecturally challenging design intent. Linking Grasshopper with Tekla Structures, for example, results in constructible, information-rich structural models that can be used throughout the project lifecycle.

As BrIM models are always up-to-date, as the model automatically updates after each revision; there is no need to update drawings manually and the production of all structural documentation is at the touch of a button. These changes can then be shared with other project members at every stage with minimal effort.

What’s more, quality assurance is also improved by correct quantity take-offs, saving human hours and money; clash checking ensures that the different models fit together perfectly before the project goes on site and the accuracy of the bridge design results in constructability and confidence.

Data-driven collaboration

It’s an uncomfortable fact that an average of 40% of site work is unproductive and as much as 30% of construction is rework. Therefore, reaping the full benefits of streamlining the entire design-construction process requires sharing and connecting accurate design information with other project parties.

A vital part of collaborative BrIM is data standardisation, which enables the interoperability of software systems between different disciplines. The information can be consumed and shared across project parties, using software such as Trimble Connect, to add data-driven intelligence to the project.

On top of this, it is necessary to implement clear BrIM responsibilities, guidelines and procedures, as well as up skill the designers, and build transparent communication methods, such as Big Room practices, so that the owner, designers and contractors can exchange information earlier on a project. Even in the typical design-bid-build projects, the information flow from design to construction improves significantly with the use of digital collaboration platforms.

No waste in fabrication

Within infrastructure projects, 10% of material is wasted. However, with accurate, data-rich models and simulations, calculating the required quantity of materials is easy. In fact, accurate data helps parties to order the right amount of material at the right time, reducing waste and the need for excessive storage space on site.

Machine-readable data benefits steel and rebar workshops, as well as precast concrete factories too, as it helps to mitigate errors due to automation that guarantees correctness and consistency. The fabrication information can also be organised and managed according to project progress; the workshops can create on-demand reports, bending schedules, material lists and meshes, while optimising the erection sequences. Even the truckloads of bridge assemblies can be organised and optimised, and the pour units and formwork can be managed in detail to avoid wasting concrete, which is not only hazardous, but a critical environmental issue. The model-based fabrication information, which is shared quickly and easily, decreases the amount of extra hassle on site.

No errors on site

On average 40% of infrastructure projects are over budget, therefore accurate and constructible (high LOD) design reduces construction costs and improves quantity take-offs.

Realistic and always up-to-date visualisations, as well as a step-by-step simulation of the construction process, smooths the communication with relevant authorities, and scheduling based on model data helps to convey the scope of the project and its development.

Requests for Information (RFIs) and resolving issues on site can be costly, but BrIM helps to avoid both. Spotting possible clashes on models prior to starting construction, minimises expensive delays and rework – saving huge amounts of money.

Schedule simulation

With BrIM, it is possible to compress project schedules due to a more efficient workflow, accurate information and timely communication. Previously, different projects parties weren’t necessarily always aware of changes and developments in the process, but with the continuously updating and evolving model, no one is left out.

BrIM uses model information as a basis and connects the model directly to the overall scheduling features. This can reduce costs even further, helping avoid idle hours for project parties and supporting prompt deliveries. Schedules can be simulated to all project parties and corrected at an early stage.

It is also possible to simulate the erection and construction object by object, which helps demonstrate different alternatives and other dependencies in operational tasks. Indeed, better understanding of a project keeps stakeholders happy, which is a valuable benefit.

Smart asset management

A common BrIM language enables authorities, governments and industries to procure and record bridge projects better during construction. With BrIM, inspections, maintenance and repair can be managed efficiently and purposefully with all construction stages reliably documented and easily available. At the end of construction, the owner gets the data-rich as-built model for smart asset management. Unlike paper documentation, the digital documents are easy to update after construction and available without difficulties for smart asset management.

In the future, with more developed, model-based bridge lifecycle applications, smart asset management can include bridge inspections with digital data collected by tools such as mobile devices, cameras and drones. Just imagine: a bridge that alerts the owner to when it needs to be repainted, when the next inspection should be conducted or when to repair expansion joints.

One project that reaped the benefits of BrIM, was the Chenab Bridge project in northern India. Being constructed as part of the new Baramulla – Srinagar – Udhamptur railway, Chenab Bridge is one of the highest (by deck height) and longest-spanning railway bridges of its type in the world. Erected on Himalayan bedrock with foundations approximately 40 metres high and 50 metres wide, the arch and piers of the bridge are masses of steel trusses, while the foundations and the approach viaduct piers are made of concrete.

As the new railway bridge is being built under extremely demanding conditions and will continue to face an array of challenges, at the beginning of project the client, Konkan Railways Corporation, stated that BrIM was to be used to create an innovative design and ensure effective co-operation between all parties involved.

As such, WSP Finland, the designing consultant on the project, chose to use Tekla Structures software, as it contains precise, reliable and accurate information needed for successful BrIM and construction execution; it also creates more accurate ways of working and streamlines collaboration between all parties.

On this project, using Tekla Structures allowed WSP Finland to organise the plate material for better logistics in the difficult terrain; it made it easier to receive the approval from local authorities too, thanks to the visualised 3D models, which were more practical to present in meetings than 2D drawings.

Tekla Structures also increased efficiency and optimisation on this project, thanks to its extensive range of connections and automated clash checking, which exposes conflicts at an early stage. The designing consultant could also execute reinforced concrete, braces, elements and block constructions, and due to its dimensional accuracy and steady coordinates, the end result was reliable and as expected.

Unsurprisingly, the design practices in bridge projects have gradually moved towards model-based design, as visualising information makes it easy for all parties to understand the process, and in the planning period the components can be associated with scheduling information.

Learn how Tekla Structures can help with your next BrIM project