The Jiaojigou Debris Flow's Development Character And Fatalness Evaluating About Dadu River Huangjinping Power Station

On the left side of Dadu River Huangjinping hydropower station to be built and around the station 315 meters, there stands a debris flow ditch— Jiaoji ditch, which is 13 kilometers long. So investing Jiaoji ditch debris flow's nature characteristic and surroundings, predicting the happening possibility, the breaking out scale and its danger, and analyzing the influence on the hydropower station are necessary.In the full text, are there seven parts of the introduction, the development environment of the debris flow, the debris flow development character, the happening easily degree of the debris flow, the moving and dynamical characteristic of the debris flow, the scale of the debris flow and the hazard appraisal of the debris flow. It tells particularly the debris flow's the environment and the development characteristic by the numbers. And according to its character, selecting the latest research results at present, the author calculates the debris flow's the moving, dynamical characteristics and the scale, such as, the velocity of flow, the wallop, the peak value flux, and the total flux. Since the happening easily degree of the debris flow is the possibility of the debris flow happening, the author defines the happening easily degree's thinking thread: firstly, it must be made sure clearly whether the ditch is debris flow ditch or not, then on the basis that it is confirmed debris flow ditch, its severity is calculated, and the possibility of the debris flow breaking out under the district rainfall condition must also be reckoned. Only in this way can the comparatively understanding be done. That is necessary to the debris flow preventability and cure, as well as the debris flow warning. It is known that debris flow hazard degree is the possibility of the debris flow impairing, and the debris flow destructive effects mainly consist up impact and deposit of two aspects. In the thesis the momentum replaces the scale to be used to calculate and analyze the debris flow hazard degree, as not only make the function of depositing of the debris flow reflected, but also is general to contain the impact of the debris flow destroying function. Because the happening easily degree of the debris flowis added to the hazard degree formula and the debris flow frequency value is weaken in the formula, it is greatly close to hazard degree meaning.In the light of the research of Jiaojigou ditch debris flow coming into being conditions and the debris flow activity, deposit extent, according to "the general analysis, the reasonable division, the security economy" principle, in the reservoir being stored water state, the debris flow pileup areas are divided into two parts of grade I hazard area and grade II hazard area, and in thfc reservoir not being stored water state, the debris flow pileup areas are divided into two parts of general hazard area and relatively more hazardous area. With jiaojigou debris flow hazardous zone analyzed, the debris flow can not have a direct bad effect on the hydropower station, except that it augments the deposit in reservoir and the station rapid flood, as well as that its cumulus shape and scope threaten the dam and the water inlet. Thus these can offer the hydropower station design, operation and clearing deposit with reference.