Risk Judgement And Prevention On Debris Flow Of Chaancun In Dalian City

Chaancun landslide in Dalian city is located in north of the Lv’shun Mid-way,whose traffic flow is large and on which the Wangjiadian Reservoir was built. And onthe mountain are the hiking corridor while down are the leisure plaza and manybuildings besides large personnel flow. There is a gully on the landslide, whoseleading edge is the landslide, and the fracture zone of the fault itself and years ofweathered gravel provided a rich source of materials for the potential debris flow. Andat the same time, the terrain condition was not good for the rickle steady, and theprecipitation in the region was great without any protection projects. As a result, if itformed debris flows which had great possibility to destroy any protective measures,with conditions mature on all sides, it would directly cause serious geologicaldisasters. However, if we studied some place with no chance for the debris flowhappening, but with some associated protection constructions working, it would addmore unnecessary financial costs and human input, resulting in waste. Therefore, itwas significant to conduct the debris flow risk assessment on the research area.Based on the fieldwork investigation, the paper introduced the geologicalenvironment and the debris flow development conditions of the research area, andthen conducted the risk assessment with the fuzzy math, giving the treatmentrecommendations bounded with engineering and biological measures. The specificconclusions were as follow:1.The debris flow curvature was small while the longitudinal slope was large.And the rickle consisted of the fault fracture zone gravel and weathered sedimentsprovided the material source. And the precipitation was concentrated and intense. Allthe reasons above facilitated the formation and development of the debris flow.2.The risk factor with the primary fuzzy evaluation was0.429belonging to RankHigh while that with the secondary fuzzy evaluation was0.408belonging to RankHigh, which coincided with the field survey results.3.Taking into long-term account, the debris flow disaster could be avoided bybuilding a concrete dam on the ditch crossing with the gutterway setting and plantsplanted on the bare area.