Laser Scanning survey and photogrammetry reality model of bridge and surrounding areas for engineering design


The road bridge over the train line at Westmead was due for replacement. A key challenge for the project was the inclusion of services utility infrastructure, such as gas, water, electrical and HV feeders, which were affixed to the bridge. As part of the construction scope, a plan was needed for the relocation of such service infrastructure without disruption to users.

As part of the tender process, Sydney Trains wanted to provide a reality model of the site and surrounding areas to reduce the reliance on site inspections and provide detailed upfront information to reduce the chance of downstream variations and cost blowouts.

Laser Scanning
Laser Scanning
Point Cloud and Reality Model
Point Cloud and Reality Model



Diodrone utilized a combination of drone based and conventional reality capture technologies to provide a 3D reality model and survey of the site.

By capturing a reality model and high accuracy survey of the current site, it reduced uncertainty and the need for track access.

Photogrammetry was used to create the 3D reality model of the site which provided a rich visualization of the bridge, 800m of rail corridor, and roadway approaches on either side of the bridge.  This reduced the need for track access and reduced uncertainty for construction scoping.

Terrestrial Laser Scanning was used to deliver an as built survey of the bridge and abutments, including services utilities affixed underneath the bridge. This enabled more accurate design scoping and project planning.

Data was captured during 1 day on site during possession period to allow for access to the underside of the bridge.

Photogrammetry reality model of bridge road over rail line
Photogrammetry derived reality model provided a rich visualization of the bridge and surrounding areas to reduce the reliance on track access and reduce uncertainty in the planning stage.


Terrestrial Laser Scanning survey derived point cloud of bridge road over rail line for engineering design purposes
Laser scanning survey of the bridge, including affixed services, delivered a high accuracy point cloud for use in engineering design, providing more information in the upfront planning stage of construction works.