Loess Area Highway Slopes Erosion And Countermeasures

Washout by flood of the highway is one of the main forms of the highway disaster. Because of the special engineering quality of loess, it is particularly outstanding that the prevention and drainage technology of highway in loess area. Further investigate the mechanism of Washout by flood, influence factor and rational protective countermeasures and engineering measures of highway in loess area is very necessary.According to special configuration and land feature , geology and climate factor of the environmental factor of washout by flood of the highway in the north of Shaanxi Province loess area, combining characteristic of loess, the paper analyzed the law and peculiarity of the loess erosion and researched some factors that influence the road bed out wash of loess. At the same time through the artificial imitated rainfall test, the paper study some main influence factors about spread flow erosion of embankment slope.Combined a large number of on -site investigate and survey data of loess area in the north of Shaanxi Province, the paper analyzed the influence factors and interrelationship of slope erosion, then put forward the main influence factors , the peculiarity of outwash destructions the main style and protective measures about slope erosion of highway in loess area. The first: the emphasis about protective measures of cut-slope are the selection of rate of grade, the place of plain stage of slope, the slope protection; the second: the emphases about drainage of cut-slope is the rational installation and mating of drainage establishment; And following this principle: the effective holding up , the rapid obviating, the smooth articulation, the seepage prevention and prevent erosion.Through analyzing and concluding those already data and the artificial imitated rainfall test , the paper put forward the main influence factors of the embankment erosion : the quantity and kinetic energy of rainfall s the shear strength and water content of soil, the catchment of pavement s the grade line and rate of grade. At the same time the paper got some conclusions : The larger to degree of compaction , the smaller to the amount of erosion; When the water content is slightly greater than the best water content ,the erosion is reduced; If it is long for rainfall to last, the amount and intensity of erosion will increase.Combined the disciplinarian and influence factors of outwash of road bed slope and the main influence factors about spread flow erosion of embankment slope, the paper put forward some principles about drainage design in loess area. These Principles will give some references on prevention and drainage technology and prevention and cure countermeasure of washout by flood in loess area.