Prediction Of Hazard Range About Debris Flow In Erdao-baihe Area

China is one of the debris flow most widely distributed, the largest number and mostserious damaged country of the world. Debris flow disasters could cause huge loss to people’slives and properties, it has been restricted the construction and economic development ofmountainous area of our country. For purpose of decreasing the harm of debris flow, it willhave important theoretical and practical significance for having prediction studies of hazardrange about debris flow.In this paper, on the basis of analyzing the domestic and foreign related researchliterature, the author had field investigation, laboratory test and model simulation test, gave theprediction of hazard range about debris flow in Erdao-baihe area. The major achievements areas following:1. With collecting and organizing the materials of field investigation and test, the mainloose deposit of Erdao-baihe area was known as pyroclastic flow deposits, the provenancesection gradients of debris flow were around5°～20°, running section gradients were around15°～25°, it has the basic conditions of debris flow.2. Provenance section gradient, running section gradient and accumulation sectiongradient was used as single influencing factor to accumulation feature respectively duringsimulation experiment, and grey correlation analysis was used to study the relevance betweenthree sections gradients and the maximum accumulation length, width and thickness ofdeposition fan. The analysis result shown as: the gradient and length of accumulation sectionwere in direct proportion to the area of deposition fan; the gradient and width of provenancesection were in direct proportion to the thickness of deposition fan. Sensitive factors analysisresults shown as: the influence factors of accumulation length were ordered as: accumulationsection gradient>provenance section gradient>running section gradient; the influence factorsof accumulation width were ordered as: provenance section gradient>accumulation sectiongradient>running section gradient; the influence factors of accumulation thickness wereordered as: accumulation section gradient>provenance section gradient>running sectiongradient; the influence factors of accumulation area were ordered as: running section gradient>accumulation section gradient>provenance section gradient.3. Provenance section gradient α, running section gradient β, accumulation sectiongradient θ and water yield V were all considered commonly during simulation experiment.Based on mathematical model form established in single factor experiments, MATLABsoftware was used to do the multielement nonlinear regression fitting of the simulationexperiment results, and the predictor formula of hazard range was established. The resultsshown as: maximum accumulation length, width and area of debris flow deposition fan werein direct proportion to accumulation section gradient and provenance section gradient, therelation formulas between running section gradient and water yield are shown as:4. Prediction formulas in this article were used to predict the debris flow of Xinglongvillage, Antu country. The prediction results were shown as: prediction error of maximumaccumulation length is5.26%, prediction error of maximum accumulation width is7.14%,prediction error of maximum accumulation thickness is23.81%, prediction error of hazardrange is1.51%. These results were more closed to the physical truth than the predictionformula in Specifications for Survey of Debris Flow Disaster Prevention Project and Likuo’sformula.