Characteristics And Governance Research Of Shanxi Loess Geological Disasters

In this paper through the research in some areas of Shanxi Province andcollecting local data of geological disasters occurred, investigating thegeological disaster site and collecting soil samples and doing laboratoryexperiments. Research results show that Shanxi loess geological disastersshowed significant regional characteristics, Shanxi Xinzhou, Luliang, Linfenarea show:(1) Shanxi loess geological disasters influenced by the local terrainconditions, weather conditions, lithology, hydrology geological conditionsgreatly, and the main types of geological disasters also will be different indifferent regions. Southern of Shanxi, the type of geological disasters includingunstable slopes, ground subsidence (including ground fissures), collapse,landslides and mudslides, but the main are landslides and collapse. SouthernLoess thickness, topography cutting heavily and exist lot valleys, a largernumber of high and steep slopes, and built new rural construction and industrialenterprises and more along the loess gully, roads, build kilns cut slope and otherhuman activities has become a dominant disasters factor., the loess in southernof shanxi is thickness, and there a great number of slopes, human activitybecomes the main factor in disasters. The number of Unstable slopes islarge,when the ice melt and heavy rainfall happen its stability will be damaged.Northern Shanxi geological disasters include unstable slopes, collapse,landslides, mudslides, ground subsidence, land subsidence, but the main are collapse and landslides. The northern region is relatively rich in mineralresources, exploitation of mineral resources caused the ground subsidence.Analyzing the population threatened we can know that most of them gather inthe areas where lots of unstable slopes, ground subsidence.(2) ShanxiGeologicaldisaster shows a significant sensitivity ofrainfall. collectinginformation on geological disasters when rainfall occurs in Shanxi Province, thedata show: The western Shanxi Province75%of geological disasters influencedby the rainfall; Geological disasters occurred mainly in June to August, in thisperiod rainfall increased significantly, and the number of geological disastersincreased heavily;10days before the disaster occurred the cumulative rainfallreached100-200mm,and the happen probability of landslides and collapsereached84.7%;when spring coming the ice in loess melts, the water contentIncreasing will cause geological disasters.Through sampling in disaster site and making samples of different watercontent to do laboratory experiments, and analysis the water sensitivity ofShanxi loess. Direct shear test data show that: There are two regular relationshipbetween shear strength and water content of shanxi loess, The first is with thewater content increases, the inverse relationship between the cohesion of the soilcontaining and the amount of water downward, and the internal friction angletended to increase, The second is when the water content between the naturalwater content and plastic limit, the cohesion of the soil decreased significantlywith water content increases, when the moisture content exceeds the plastic limitdoes not change more,and the internal friction angle increases little with thechange of water content. analysis shows that soil shear strength influenced bythe water content, water content can easily lead to an geological disasters, whenthe water content in the soil exceed the plastic limit can be used as an earlywarning reference of geological disasters.