Brookfield Rail Line Survey
Brookfield Rail Line Survey
Overview
AAM were commissioned to survey 188 kms of optimised rail line from Tilley Siding, Morawa to Narngulu Yard in Western Australia. The as-constructed survey required capturing the main line and passing track’s alignment amongst other services. An accuracy of +/- 0.03 or better was also required within an eight-week timeframe.
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The Challenge
The optimised line required detailed existing condition information to capture and process required survey data leaving adequate time for design. Assigned an eight-week deadline, AAM was forced to utilise an unconventional survey technique. The ability to extract additional information from the dataset was desirable, with as-constructed data used to confirm the construction and design without significant variation.
Any variation claims previously expressed could also now be validated. The remote location and limited rail line access due to freight movement required solutions to be robust and repeatable.
The Solution
AAM deployed Mobile Laser Scanning (MLS) technology to capture point cloud data, with spherical imagery over the entire railway corridor. Our scanner additionally captured other extractable infrastructure and services including:
- Level Crossings
- Signals
- Switches
- Bridges, and
- Culverts
We captured data in MGA94 and AHD with the MMS system including a number of electronics mounted onto the rear of a hi-rail track vehicle. With Brookfield Rail’s assistance, the laser profiler, spherical camera system, GPS and inertial measurement unit (IMU) were attached to the hi-rail vehicle.
Ground survey was required in support of the MLS operating along each track section, including visible targets at 500 metre intervals, GPS base stations and ground test points.
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The Results
With three passes of the MLS, significantly more data was captured with greater accuracy and confidence. Comparing the MLS point cloud to the field test points confirmed accuracies of better than 0.03m horizontal and 0.04m vertical. High resolution spherical imagery was delivered with a customised georeferencing viewer.
Survey deliverables included detail rail alignment and formation, feature extraction from the scan data and earthworks volume reporting.
Typical Scan Data Work was performed to strict Safety Standards in accordance with Brookfield Rail requirements. The MLS data supported immediate commissioning of the rail line and the ongoing maintenance and management of the rail corridor.