Abstract
Recently, population and development approach closer to mountainous regions and other landslide prone areas. Since landslides produce loss of life and damaging to property, monitoring and analysing the runout behaviour of landslides using numerical models becomes crucial. In Scandinavian countries, quick-clay slides are among the most catastrophic events compared to other landslide types. Therefore, the main objective of this thesis is simulation of landslide runout in cohesive soils. A synthetic benchmarking and the Finneidfjord quick-clay slide were considered as case and were simulated using the DAN3D and BING models. The models are totally based on topography and material parameters. Synthetic benchmarking simulation was done using both rheologies of the DAN3D and BING models. Runout distances and flow velocities were analysed and showed reasonable results. However, using DAN3D Bingham rheology the maximum runout extends beyond the domain of the simulation. In the BING simulation the end of the simulation time was very small compared to the DAN3D model. Runout distance is the longest in DAN3D model simulation using plastic rheology and maximum velocity is the highest in the BING simulation. The Finneidfjord quick-clay landslide was simulated using both plastic and Bingham rheology in the DAN3D model for two different volume of initiation. The lower and higher volumes used were 945,000 & 1,220,000 m3 respectively. This landslide was also simulated using the BING model. Runout distances and flow velocities were analysed for each cases. Runout of the simulation was compared with plastic rheology for the first 200 seconds and it was found that runout in the case of Bingham was shorter. In general, the runout distance was longer for case of DAN3D model and the maximum velocity occurred in the case of the BING model. Simulations using plastic rheology in the case of DAN3D and BING have shown reasonable results compared to the Bingham rheology using DAN3D.