Combining digital terrain and surface textures with large-scale particle-based computational models to predict dam collapse and landslide events

Computational modelling of extreme rock and fluid flow events, such as landslides and dam collapses, can provide increased understanding of their post-initiation course. This can provide valuable insight into opportunities for designing mitigation strategies and to enable more informed management of such disaster scenarios. For the prediction of fluid-based geo-hazards, such as dam breaks, the smoothed particle hydrodynamics method is ideally suited to predicting the resulting complex highly three-dimensional free surfaces flows, which involve splashing, fragmentation and interaction with complex topography and engineering structures. For landsides, which are collision dominated flows of rocks, the discrete element method provides an ideal method for prediction. In all cases, the quality of prediction is controlled by the availability of high-quality digital terrain data produced typically by photogrammetry. Interpretation of simulation results is enhanced when photogrammetric-based surface textures are used in the surface renderings for flow visualisation. Advanced geo-hazard modelling therefore requires a close combination of both photogrammetry and particle-based modelling. Two case studies of dam breaks and one landslide event are used to demonstrate the level of prediction that is now possible using these combined methods.