Methodological Research on Numerical Simulation and Disaster Risk Assessment of Debris Flow Deposition Fan

Author: Luo Yuanhua & Chen Chongxi
Language: Chinese
Published on: 2000-01
Paperback

This monograph focuses its research on the advanced areas of numerical simulation and disaster risk assessment of debris flow deposition fan. On the bases of its research achievements, a systematic methodology has been established for the assessment of disaster risk of debris flow deposition fan.
With respect to numerical simulation of debris flow deposition fan, the previous studies has been reviewed in this book. Set up the mathematics model with describing the process of two-dimensional debris flow, authors develop the contimuity equation by the law of conservation of mass and establishe the momentum equations by the law of conservation of momentum. The authors make good use of the advanced computer technologies, establishe the finite difference equation of numerical simulation by the differential operator fission method, and write programs for computers which contact friendly with the other programs. The parameters are directly input on the keyboard. The numerical simulation process is correct and stable. The whole programs can be used commonly and be expanded easily. Comparing with the results of the laboratory experiment and the data observed in the field, the results of numerical simulation are identical. The deposition process by numerical simulation is in keeping with the law of debris flow movement.
With respect to the disaster risk assessment of debris flow deposition fan, the authors promote their main ideas by summarizing and analyzing the relevant techniques and methods for its assessment. On the bases of a research on the preconditions of debris flow deposition fan and allocation of the disaster areas, the authors lay their foundation on the assessment of the degree of danger, regards the assessment of injured degree as the main part of his research and the assessment of disaster loss and efficiency in preventing and reducing the disaster as its research findings. Finally, some proposals for the decision maker are putforword. According to the findings of numerical simulation and with the example of Nilagu river in Dongchuan city of Yunnan Province, the author promotes the concept of danger and injured degree and its calculating methods in assessing the degree of disaster, which can be used directly in assessing and estimating the losses on the debris flow deposition fan when a certain degree of debris flow disaster is coming.