| Summary: | Physical barriers are effective tools in the mitigation of landslide hazards. Numerous case histories have been reported where flexible barriers have successfully contained debris flows, and more recently debris avalanches up to 10,000 m3. The current limitation in the design of such measures is quantifying the force imparted by the landslide on the structure. Standard practice limits the investigation to flow parameters, neglecting the behavior of the structure, which can significantly vary between designs and installations. Effort has been made to model the flow – structure interaction, but has thus far been limited to complex numerical models. This research focuses on the development and validation of a simple, numerical model to quantify the total force imparted by a flow-like landslide on a flexible barrier. The model is based on a previously validated code for analysis of landslide mobility, DAN-W. The current model, referred to as DAN-Barrier, uses stiffness as a key physical property of the flexible barrier. The numerical solution explicitly solves for the total force, fill height at the barrier face, and barrier deflection during each time step, and the landslide mass reacts to the addition of the barrier force resisting flow. In an attempt to validate the numerical model, a series of flume tests have been performed where granular material impacts a rigid wall and a flexible rubber barrier. With some calibration, reasonable results are obtained. The model was also used to simulate forces induced during full-scale impacts by back analyzing experiments performed at debris flow and debris avalanche test sites. DAN-Barrier requires further refinement and calibration before it could be used as a predictive tool, but is successful in showing the potential for a simple tool to quantify the flow – structure interaction that occurs when flow-type landslides impact flexible barriers.
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