Study On Characteristic Of Blown-sand Hazards And Preventive Measurements Along Taiyuan-zhongwei-yinchuan Railway

Since the opening of Taiyuan-Zhongwei-Yinchuan Railway, the blown-sand hazardsalong the line are worsening. The normal use of railway equipment in the piled sang will beaffected. Piled sand even pose a threat to traffic safety in some serious areas. Through theinvestigation of Taiyuan-Zhongwei-Yinchuan Railway which be managed by the LanzhouRailway Bureau, there are nine areas belongs to first-class sand hazards and thirteen areasbelongs to second-class sand hazards, the total length of these parts is58km, and theaeolian-sand disaster is very serious and it incessantly jeopardizes the railway operation.Thelength of the sand hazards is very long, the sandy desert range,the harm degree, the causes ofsand hazards and the climate envirment is different. So every sandy desert area must beinvestigated and researched carefully. According to the situation of every sandy region, inorder to design targeted sand-prevention system, and make sure that the sand-preventionmeasures adjust to the local condition and the characteristic of the wind-sand disaster.This paper researches on the protective effect of sand-prevention system which in theexperimental area of K1563＋500——K1566＋850. On the basis of field survey, consider thesand transport rate and wind speed data, and according to unique natural climatecharacteristics in the desert region, such as regional climate harsh, heavy wind-sand, dry andless rainy, high temperature difference between day and night, and scarcity of buildingmaterials, transportation inconvenience and heavy engineering cost in the desert region. In thepremise of meeting the protection requirements, we propose and implement combiningengineering with plant integrated prevention system. Meaning, by laboratory test, fieldobservation, field survey and research methods, we make a evaluation of existing sandprevention measures in the MeiHuaJing. In order to solve the problem of existing sandprevention system and measures, we make some suggestions of improving the sandprevention measures and perfecting the sand prevention system.Main research contents and conclusions: through the investigation ofTaiyuan-Zhongwei-Yinchuan Railway which be managed by the Lanzhou Railway Bureau,such as desert distribution, the cause and hazard rating of sand hazards, the climatecharacteristic, the type and coverage degree of the original vegetation, the sand flow activitiescharacteristics and so on. The main sandy hazards type is proposed in detail, which are sandyland and desert. There are two main hazard type, first is wind-drift sand, the other one ismoving dune bury. According to the characteristic of sandstorm activities alongTaiyuan-Zhongwei-Yinchuan Railway, on the basis of sandy region’s specific circumstance, such as the scope of the dune, the distance and range of the outside dune, the coverage degreeof the original vegetation and so on. Follow the principle, which include the sand-preventionmeasures should adjust to the local circumstances and integrate engineering measures withplant, propose three kinds of prevention and controlling and hazards model, which aredegradation of pasture model, desert model and sandy land model. We constractsand-prevention engineering measurements in the MeiHuaJing area, such as block sand belt,straw and nylon checkerboard sand-fixed belt, and according to the local environmentalconditions and the plant situation, we plant trees and grasses among the straw checkerboardsand-fixed belt, set up comprehensive-prevention system which contain engineering and plantmeasures. Through long-time observation and research shows that these measures play asignificant role in terms of cutting the wind speed, preventing and fixing sand, decreasing therate of dune movement. Under the protection of engineering measurements, the vegetationcoverage in the experimental area increases10to15times which forms the vegetalsand-prevention system, and the sand hazards had been controlled sufficiently.