Bridge information modelling (BrIM), or BIM for bridges, is an advanced methodology for the bridge design and construction industry
Intelligent, physical 3D bridge models provide a perfect graphical and functional representation of a bridge and its design results, improving design quality, constructability, and collaboration.
BIM for bridges is increasing in popularity, with several US State Departments of Transportation adopting BIM workflows for bridges and Bentley’s OpenBridge. The New York State Department of Transportation (NYSDOT) has recently released its first “model-based contract” where the intelligent 3D bridge model plays a central role. This contract approach minimises the use of paper plans, requiring that project bidders use a digital copy, a 3D model of the entire project that contains topography, geotechnical, roadway, and bridge information. The Iowa DOT and Utah DOT have also completed transportation pilot projects that required the provision of 3D intelligent models as deliverables, utilising BIM practices.
Take advantage of collaborative software
Leading DOTs and progressive consulting firms are taking advantage of innovative collaborative software applications to eliminate traditional workflows, where bridge and roadway designers work in silos with very little information sharing or reuse of data. For example, terrain data and roadway geometry are generated by roadway engineers, and this data is shared with bridge engineers via paper copy or methods that require manual data entry or export into a new format. This traditional workflow introduces unnecessary project risk with the potential for inaccurate or outdated data entry, resulting in delays to the project schedule and cost overrun.
Traditional, non-interoperable workflows create a range of disconnected models, including visualisation models for marketing or public information purposes, CAD models for geometry verification, and structural analytical models for design calculations. Any changes or updates to these models must be done independently, resulting in a workflow prone to data entry errors and diminished data ownership and modifications tracking. This situation leads to a decrease in productivity, as well as liability conflicts.
Digital project delivery with BrIM
Using 3D intelligent models to represent physical bridge information offers owners of bridge assets the opportunity to use digital project delivery, including 3D visualisation, virtual assembly, automated machine control, fast routing and permitting, network-level study, and smart inventory as a routine part of project development and asset management.
BIM for bridges not only encompasses the creation of an intelligent physical 3D model, but also establishes an environment for all applications required for bridge design to interoperate and efficiently exchange information. Therefore, the intelligent 3D model becomes the single source of information for the project, allowing different engineering disciplines and sub-disciplines to retrieve specific data and update the 3D model.
As bridge information modelling practices become mainstream, it is clear that the hundreds of potential information exchanges taking place over the lifecycle of any bridge—spanning design, construction, and management phases—can gain significant value by leveraging 3D intelligent models.
While there is high initial value in preparing and automating bridge design plans, production of 2D plans cannot be the ultimate goal of BrIM. The real value of bridge information modelling lies in the virtual elimination of 2D plans and the transition to a fully digital solution, adding more information like material descriptions, design specifications, reports, and geotechnical data to make the model more intelligent.