ETH Zurich and SLF build 3D printed rock avalanche scale model
The 1:577 terrain replica lets researchers run controlled tests of how rock, ice and water move downhill
Researchers at ETH Zurich and the WSL Institute for Snow and Avalanche Research SLF have built a 3D printed scale model of the Blatten area to study how mixtures of rock, ice and water move during avalanches and debris flows.
The model, at a scale of 1:577, reproduces the terrain where a rock avalanche destroyed the Swiss village of Blatten in 2025, and is housed in a former military bunker near Davos.
The terrain was printed in 56 separate segments, each roughly 50 by 50 centimeters, that were assembled into a surface covering about 12 square meters across a maximum footprint of 5.4 by 4.5 meters.
Production of the full set of printed parts took approximately 100 days, with Johan Gaume, Professor of Alpine Mass Movements at ETH Zurich, leading the research group at SLF.
Replacing field observation
In each experiment, researchers mixed water, sand and clay in calculated proportions and introduced up to about 48 liters of the mixture through a hatch at the top of the model, on an inclined section measuring 4.5 by 2 meters.
The material could travel a horizontal runout of up to 6 meters, with a maximum input mass of 1 tonne per test. Cameras, lasers, 3D scanners and sensors recorded runoff depth, flow speed, travel distance and impact forces as the material moved across the printed terrain.
“We want to use models like this to find out how mixtures of different materials move in the natural environment,” Gaume said. “For these models to be reliable, they must be thoroughly tested in carefully controlled experiments.”
The experiments are intended to improve the computer models that regional authorities use to assess hazard risk to settlements and infrastructure from rock avalanches and debris flows.
“This is a long-term investment in research, not a short-term experiment,” explained Gaume.
Future work will examine erosion, the effect of obstacles in a flow’s path, and how terrain curvature shapes flow behavior. “At the moment, we’re especially interested in the influence of terrain curvature on flow dynamics,” added Gaume.
