High resolution Drone LiDAR survey of Illawarra Escarpment for geotechnical assessment and road stabilisation design
One of the main arterial roads that descends the Illawarra escarpment includes several known geotechnical risk sites including rockfalls, shallow landslides and embankment failures. Drone LiDAR survey of the road corridor and adjacent slopes was required to inform geotechnical assessment and stabilisation design. The steep and heavily vegetated nature of the site precluded access for conventional survey methods, beyond the extent of the immediate road corridor, and additional information was required by engineers and geologists working on the project.
Diodrone developed a survey solution which utilised drone LiDAR to develop a high-fidelity digital terrain model (DTM). The temperate rainforest, typical of the Illawarra Escarpment, had a very dense vegetation canopy and so drone LiDAR capture was carefully planned to maximise ground returns and point cloud density.
Diodrone’s LiDAR capture achieved an average point density of 500 points/m2 and provided sufficient ground information for terrain modelling, even in areas of the extremely dense vegetation. When assessed against a network of control points established throughout the road corridor, Diodrone’s deliverables achieved an accuracy of better than 50mm RMSE and included high resolution topographic detail of slopes which are otherwise inaccessible and unknown.
Despite a dense vegetation, Diodrone was able to achieve high resolution topographic detail at better than 50mm accuracy.