Transposing construction site information and keeping it in a digital value chain

BIM file series @ SGI

By Thomas Eglinger, BIM manager at SGI

For more than 50 years, SGI Ingénierie SA Luxembourg has been active in the field of engineering: building structures, technical engineering, infrastructures, engineering structures, construction management, health and safety coordination, and project management. The company employs a hundred of people, each tasked with ensuring the success of its clients’ projects – from design mission to field supervision.

For this new contribution in our ongoing blog series entitled “The BIM Files @…” we asked Thomas Eglinger, BIM Manager at SGI, a multidisciplinary European engineering group based in Luxembourg, to share how his firm used BIM technology to track back so they could build forward.

The BIM approach at SGI

For over 12 years, I have worked in project management, providing development and services for a range of clients. Since 2018, I have held the role of BIM Manager at SGI.

To encourage what I call “BIM Thinking,” I also lead a BIM internal development effort and share my expertise at external events, including the BIM Lux trade fair, conferences, and canvassing clients. I am also a CRTI-b and IFSB BIM trainer and work with universities in France as part of a pedagogical committee and as a thesis director.

Why? I believe BIM is a crucial technology for all phases of a construction project – it’s how we move the project forward through all the key stages. And for one particular project at SGI, the BIM allowed us to recreate the past in the present tense so we could create the future.

Parking des Martyrs – not your typical project

Built in 1981, The Martyrs Car Park in Luxembourg consisted of three underground levels, comprised of 11,000m2 of space. Until September of 2019, when a fire broke out in the car park.

What sparked the need for … a retrospective BIM

The city of Luxembourg (the department Service Ouvrages d’art) saw its potential still and wanted to rehabilitate the damaged car park. A noble cause, but one that came with quite the challenges for the construction engineers tasked with assessing and executing the job:

1. The renovation of this “structure” (the car park is not considered a building because of slopes) held its own complexity. It included hundreds of beams, slabbed and sloped floors, and integrated sloping reservations. Moreover, there was deformation due to the age of the building.
2. Generic modelling could not outline the project as a whole, which complicated existing and future project integration plans and the coordination between the architect and the engineering offices.
3. The different construction types and structural deformations, forces the team to focus more on the structural model and less on the architectural model.
4. To free up more time for the design teams, SGI first had to create a digital model from pre-existing input data, including 3D scans, period execution plans, and surveys.

As the modelling of this pre-existing data progressed, even more challenges arose. Though not an actual reality, BIM modelling is a representation of the reality. Unfortunately, it was not in the time and financial scale of the project to model all the 317 TT beams according to their deformation after 50 years.

Information like reservations in selected places and the corbels’ state was crucial, but only an expert engineer could identify them. There was no budget for a dedicated software expert to make it happen and most georeferencing tools they looked at did not offer what they truly needed.

So, now what?

SmARt Viewer to the rescue for a retro-BIM success

My objective throughout this project to experiment an ideal BIM environment – realising a Retro-BIM and gradually progress it into an overall sustainable BIM process.

To make this happen, we needed to reinforce coordination and collaboration around the model and use the right tools so we could create the perfect output for the customer:  a digital as-built which validates the project now as is, but also makes it futureproof.

That’s the challenge I set myself out to achieve, and why I started onboarding digital and cloud-based solutions to create a lean and integrated digital process.

It’s why I selected Axeobim as our selected CDE platform and why I approached GenieVision. I needed an AR solution to visualise each model and/or site surveys done on site by the BIM manager or the engineers.  This SmARt viewer would easily feed the model with geolocated pictures, speeding up the entire control process instead of doing it manually without any option of gathering all images or notes on a central location. It’s a portable solution, enabling all people on site to work offline while being connected to our existing systems in standardised ISO formats. The information is also stored on a cloud platform and can be accessed at all times by “non-BIM expert” users.

I was always a strong advocate for using BIM processes to improve the management of our projects. And in this case, I believe the retro BIM will prove essential to solve this specific repurposing challenge and help meet the unique demands of this project and improve overall project coordination. Our work on the car park illustrates yet again the crucial role BIM plays in tracking and matching actual situations, and how to actively use it to enhance refurbishing outcomes. Especially when leveraged with AR.