Creating High-Resolution Digital Terrain Models to Help Design Rockfall Barriers

Rockfall is one of the most common causes of disruption in transportation corridors, sometimes endangering lives. High-resolution Digital Terrain Models (DTM) are widely used to characterize the cliffs and identify the paths where rockfalls may occur. They are used as the base to design dedicated barriers. The multi-echo technology of a Lidar payload it allows penetrating the layers of vegetation to measure the ground points and model the terrain and the rocks underneath. Installing a Lidar payload in a multicopter drone is quick and easy in the field and makes it possible to investigate in multiple surveys over time the changes in the cliff configuration that may lead to rockfall events, and design effective countermeasures.

The project

Tecno Proget srl used Scanfly XT to investigate the cliff faces above the small town of Provaglio d'Iseo, in the Franciacorta region of Italy. The cliffs threatened the properties underneath and the corridors of the highway and the local railway.

Purpose

 The Lidar survey of the area was performed to generate the DTM of the area, analyzing also the position of the rocks that could trigger an event and the position of the trees standing on the area.

Results

 The Digital Terrain Model (DTM) generated from the Lidar point clouds allowed for the design of the rockfall barriers in the most effective position, depending on the amount of material affected by the phenomenon and the position of the existing trees.

The Scanfly advantages

 The accuracy and the combined effect of the 32 laser channels of the Scanfly XT confirmed their reliability when the task is about detecting and modelling features at the ground level, underneath layers of vegetation. The UAV installation is quick and easy and provides significant advantages to the surveyor in terms of the time needed to complete the analysis.