The Engineering Effect And Evolutionary Mechanism Of Zhangjiagou Debris Flow

As the economic increasing activities of human society, the excessive exploitation and continual destruction on the environment deteriorate natural disasters including debris flow. Therefore the study, evaluation, forecast and mitigation management of the debris flow must be strengthened, economical and effective preventing engineering must be enforced. Only by this way the occurrence of the disaster can be prevented and the damage of the disaster can be reduced.The thesis analyses the circumstances of the debris flow happened in Zhang jia gou of Jiu Long county of Sichuan province in the year of 2003, which had blocked the river for 5 minutes. The thesis studies the rainfall debris flow and analyses its origin cause of formation and the law of development and evolvement through field work and spot investigation, and offer the debris disasters a systematic forecast and preventing and curing scheme.First, the thesis analyses the character of the debris flow happened and obtain the primary character. Second, according to the three basic factors, rich solid material resource, essential terrain and enough hydrodynamic, systematically predict this type debris flow inclding occurrence moment, scale and danger degree of disaster. The analysis on topographical condition is carried out in terms of valley area, the grade of the two ditch sides etc. the analysis of the incompact substances is taken in terms of fieldwork through analytic approach. The analysis of water moving force is taken by means of velocity of flow, flux, striking force etc. then the thesis obtains the debris flow development trend and project influence of Zhang jia gou, and predicts the frequency of the occurrence of river blocks. On the basis of the above researches, feasible countermeasures presented, and preventing and curing project benefit evaluation is carried out.