3D Scanning for BIM and Feasibility Study
For this project it was determined by the design team to utilize a combination of 3D scanning techniques and the power of 3D design software to communicate across the design team the options, issues and assumptions associated with this project.
Traditional survey techniques would have created a basic symbolic drawing of what was located where, but with a 3D scanning approach everything visible could be captured to assist the design and feasibility team to work within the corridor without physically being there themselves.
By capturing “everything visible” the design team could request additional information regarding structures or terrain, without the necessity of the survey team to have to revisit the site. This enables the survey team to quickly respond to any request for the multiple disciplines of the design team. If more information was required for a bridge design then the survey team could extract just that information necessary to answer the structural engineers’ request.
With the entire rail corridor scanned (5kms totalling 4.6 billion points) very few computers would be able to work with such an enormous data set. So that the design team can take advantage of the 3D scan, the point cloud needs to be segmented into disciplines. The survey team split the data into terrain, cable support structures, telecommunications, rail, signals, bridges, HV assets drainage and fence line. Each discipline was then converted into an appropriate file type via modelling or data conversion software and all of these BIM assets where then delivered geo-referenced in MGA which was the coordinate system established to be used in this project.
This approach resulted in just enough detail, of suitably small enough files, positioned in true location of exactly what is present in the rail corridor.
The benefits of this approach extend beyond just the feasibility and design team, all the way through to the options evaluation and risk management processes.