HR: 14:25h
AN: H43G-04    [Abstracts]
TI: A Physical-Based Model of Postfire Hillslope Dry Ravel
AU: * Fu, X
EM: fuxyang@mail.wsu.edu
AF: Washington State University, Department of Biological Systems Engineering, PO Box 646120, Pullman, WA 99164-6120 United States
AU: Wu, J Q
EM: jwu@wsu.edu
AF: Washington State University, Department of Biological Systems Engineering, PO Box 646120, Pullman, WA 99164-6120 United States
AU: Robichaud, P R
EM: prubichaud@fs.fed.us
AF: Rocky Mountain Research Station, USDA Forest Service, 1221 South Main Street, Moscow, ID 83843 United States
AU: Sharma, S
EM: ssharma@uidaho.edu
AF: University of Idaho, Department of Civil Engineering, Moscow, ID 83844 United States
AB: Dry ravel is a gravity-induced downslope surface movement of soil grains, aggregates, and rock materials that commonly occurs on steep hillslopes after disturbances such as wildfires. A quantitative analysis and model of dry ravel is needed to understand the behavior and effects of dry ravel movement. In this study, we developed a physical-based model based on classic mechanical laws and particle flow theory. The model predicts source locations, movement path, and deposition areas of dry ravel produced after wildfires. The short-term dry ravel process is computed with theoretical calculations, and the long-term effects are described with both theoretical calculations and empirical probabilistic characterization. We assessed the sensitivity of the input coefficients, and provide a suitable range for these input coefficients. To calibrate and validate the model, we calculated dry ravel estimates from a wildfire area in the San Dimas Experimental Forest in southern California, and compared with experimental results. The comparison shows that the model is suitable for analyzing dry ravel on steep slopes, with easily-weathered parent material.
DE: 8020 Mechanics
DE: 3367 Theoretical modeling
DE: 3010 Gravity
DE: 3210 Modeling
SC: Hydrology [H]
MN: 2004 AGU Fall Meeting