BIM, the best tool for civil engineers
Contrary to what most people might think, Building Information Modeling (BIM) is not software . Nor is it an extension. We’re talking about something more complex, something we could define more as a new philosophy or work methodology that will revolutionize the sector than a specific work tool. BIM is a process based on collaboration, coordinated, and reliable information about a project, from the design phase through construction and its final operation. Therefore, BIM is not just for architects ; in fact, it can be applied to any type of construction, from large buildings to roads, bridges, or highways, so civil engineers will benefit from all the advantages it offers.
BIM enables civil engineers to make predictions before projects are even built, adapts to and optimizes design changes with analysis, simulation, and visualization, and provides a wealth of high-quality documentation of all the elements that make up the model. Furthermore, and if that weren’t enough, it allows for coordinated work with all team professionals , thus facilitating the free flow of information.
The limitations of classic 2D drawings
Engineers have always worked with familiar 2D drawings for road and highway design. This process, which we could categorize as “isolated,” begins with a preliminary design concept, evolves into a more detailed design, and then moves on to construction documentation. Therefore, each process is completed individually, and a sequence must be followed to move from one phase to the next, thus disabling any type of collaboration. But what happens when we need to make changes? These are usually done in an archaic manner, freehand, and within the design itself, which can lead to errors. In other cases, the drawing must be completely redesigned, inexorably lengthening project times.
The graph above shows the level of effort required for a conventional highway project , from the preliminary design phase through construction to subsequent operation. Looking at the blue line , we can see how the civil engineer’s ability to influence cost and performance throughout the project lifecycle diminishes over time. The red line, meanwhile, indicates the cost of making and executing any changes to the design. In this case, its rise is inversely proportional to the blue line and increases as the project progresses. The black line indicates where engineers and designers expend the most effort , using more resources in the drawing-centric process: the documentation phase. The fourth and final line (the green one) is the BIM workflow.
As we can see in the graph, the black line coincides with a point in the project when the engineers’ ability to impact the project decreases and costs increase. Theoretically, it is possible to use this process to create iterative designs and optimize the project, but it is rarely done due to the high costs involved once documentation has begun. Therefore, the drawing-centric process generates the first design that will eventually reach code, but it is not necessarily the best.
New ways of working with BIM
Some of the most direct benefits of BIM for civil engineers include improved design management, increased efficiency, and increased productivity, among others. Because documentation is more complete and hosted on a server accessible to all project members, it significantly reduces the time it takes to evaluate the best options, changes, and alternatives during construction. This is especially useful for transportation agencies, which can see reduced lead times on lease contracts, with orders arriving sooner and with more predictable schedules.
If we can see what we’re building, it’s clear we can carry out much more efficient projects. With BIM, we have the tools necessary to virtually visualize and manage the model we want to create, for example, a highway. Thanks to this new methodology, improved construction is achieved. Engineers typically design projects with the code in mind, not so much constructability. Therefore, any error in the documentation prepared on-site leads to a delay in the pre-established deadlines for project completion.
Increasing road safety , thanks to the analysis offered by BIM, for example, to ensure safe sight distances for overtaking and braking, is another point to consider. To achieve this sight distance we mentioned earlier, it is necessary to perform mathematical equations based on the vertical curvature of the road profile. However, when performing these operations, factors such as the horizontal plane or visual obstructions are not taken into account. With BIM, we are able to integrate interactive visualization and simulation of sight distance into the design , allowing the engineer to see if the construction meets safety parameters (grades, curvatures, and obstructions such as barriers, shoulders, and foliage). With BIM, we can extend the use of the information model beyond design, analysis, or construction.
What BIM can offer to civil engineering
Improved construction and increased safety are some of the benefits of BIM for civil engineers, but there’s much more. At the Wisconsin Department of Transportation, they plan to implement AutoCAD Civil 3D for highway, geotechnical, stormwater, and bridge design teams who use customized analysis applications and tools to analyze different parts of the project. However, regardless of the efforts of the various stakeholders, the analysis and simulation phase continues to be performed in a disconnected manner, making coordination between teams difficult.
It’s now time to analyze how BIM will make its way into civil engineering. For now, BRIM is already being applied in Europe, which implements the BIM methodology in the field of bridges, as Jose Carlos Lino explains in this interview . BIM is a very powerful tool , not only for construction but also for the design phase, information management, and facility management.
