• Graphic Engineering Solutions and Services and African Consulting Surveyors

    PRASA Depot Modernization

    South Africa

Project Summary

Passenger Rail Agency of South Africa (PRASA) initiated the ZAR 100 billion program as a catalyst to transform metro rail services and public transport. PRASA appointed Graphic Engineering Solutions and Services (GESS), with African Consulting Surveyors, to laser survey and reverse engineer rail lifting and running sheds at four sites as part of a ZAR 7 billion modernization project.

GESS and African Consulting Surveyors completed scans in Cape Town, Johannesburg, Pretoria, and Durban. A total of 786 scans captured more than 19.7 billion points. Given the enormous amount of data, Bentley point-cloud technology enabled the project team to use 5 millimeter unified point clouds in the 3D modeling space for reverse engineering. The team delivered intelligent information models with billions of spatially correct points.

No traditional standard survey method could have adequately captured all of the richly detailed as-built information for these sites, much less deliver the information in less than two months. The methodology used by GESS and African Consulting Surveyors allowed design teams located around the world to start their work with accurate as-built information.

Bentley solutions were selected for their ability to run on a single platform and integrate across various disciplines. Bentley products enabled the project team to use a large amount of point cloud data without compromising the quality. Products used for 3D modeling and drawing extractions included MicroStation, Bentley Pointools, Bentley CloudWorx, PowerCivil for South Africa, AECOsim Building Designer, Bentley Navigator, and Bentley Descartes.
  • Using laser scanning, 3D modeling, and as-built drawing extraction provided accurate data for design teams to carry out the modernization of rail stock and infrastructure.
  • With these teams located around the world, the as-built models allowed virtual site visits and 3D investigations, minimizing cost and safety issues in the active workshops and sheds.
  • To make the models accessible to a range of skill levels, deliverables included point-cloud files, 3D models, structural files, 2D CAD files, 3D PDFs, and i-models.