GULLY-SPECIFIC DEBRIS FLOW HAZARD ASSESSMENT IN CHINA

Key words: 
• debris flow /
• hazard /
• gully-specific debris flow assessment /
• theore tical equation

Abstract: Techniques of gully-specific debris flow hazard assessment developed in four periods since the end of the 1980s have been discussed in the present paper. The improvement for the empirical assessment method is the sectionalized function transformation for the factor value, rather than the classified logical transformation. The theoretical equation of the gully-specific debris flow haz ard is expressed as the definite integral of an exponential function and its numerical solution is expressed by the Poisson Limit Equation. Current methods for assessment of debris flow hazard in China are still valid and practical. The fur ther work should be put on the study of the reliability (or uncertainty) of the techniques. For the future, we should give a high priority to the relationship between debris flow magnitude and its frequency of occurrence, make more developments of prediction model on debris flow magnitude, so as to finally reach the goal of assessing the hazard of debris flow by theoretical model, and realize both actuality assessment and prediction appraisal of debris flow.