Loess Cave Formation Environment And Distribution Law

Because of the development of loess tunnel, the basal construction in the loess plateau is threaten seriously. Bu: for a long time, even all attention has been focused on the loess tunrel erosion, and the thorough research on loess tunnel hazard is lacking.Based on making of field survey and researching on document, being in the light of the principle of comprehensive researching and holding tightly the emphases, the loess tunnel forming environment and distributing laws are reserched depending on geological structure,landform, physiognomy,stratum, soil, climate,the movement of the animals and plants etc. The main task ard key results are follow:Research on loess tunnel forming environment: Synthesize forefather research results, analyze to each environmental element constituting loess tunnel forming environment, such as geological structure, topography, landform, stratum, soil,groundwater, weather,and human activity etc., and find out how can they inflae to the formation of loess tunnel. Among them, soil is the primarily dominant factor.Research on loess tunnel distributing laws: according to actual field survey and summarizing documents, the divisional map of loess tunnel distributing density was made, because of tie influence of neotectonic movement, topography, landform, soil, and rainfall, territorially gradual modification was shown consuming" y in loess tunnel distribution. Yet, because of local microcosmic topography, landform, vertical variety of soil, assorted relation, joint fissure, and human construction, asymmetry was shown in tunnel local distribution. Based on the research on Loess tunnel forming enviroiment and distributing laws, macroscopic and microcosmic aspects estimate and forecast was made.