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以寒区公路路基作为研究对象,采用与天然老的细粒雪密度相似的麸皮作为模型雪,通过室内风洞试验研究雪粒子的起动以及沿路基不同部位堆积和积蚀的过程,确定雪粒子沿路基坡面堆积区域与路基断面之间的关系.通过FLAC数值模拟,考察融雪径流对路基的侵蚀作用;引入融雪侵蚀面积率,研究了融雪侵蚀面积率随融雪量、土体饱和度、路基边坡坡率以及路基高度的变化规律.结果表明:在研究地区平均风速和常年最大吹雪时间下,随路基高度增加、边坡坡率增大,路基迎风坡底和背风坡底风速降低,背风坡底风速下降显著.造成雪粒子的堆积区域主要集中在迎风坡面和背风坡面,且路基背风坡面积雪更为严重.而路基内部因融雪径流的侵蚀渗透,使得融雪侵蚀面积随路基高度增加、边坡坡率增大而加重,且融雪侵蚀面积率随融雪量增加、土体饱和度的增加而增大至充满路基整个断面.研究结果可为寒区公路量化风吹雪雪蚀路基的影响提供理论依据.
Taking the roadbed in the cold area as the research object, the wheat bran which is similar to the natural old fine-grained snow was used as the model snow. The indoor snow tunnel test was used to study the initiation of snow particles and the accumulation and erosion along different parts of the subgrade. The relationship between particle accumulation area and subgrade section along the roadbed was investigated.The FLAC numerical simulation was conducted to investigate the erosion effect of snowmelt runoff on the roadbed.The area ratio of snowmelt erosion was introduced to study the influence of snowmelt erosion area ratio on snowmelt volume, soil saturation, The results show that under the condition of average wind speed and maximum snow blowing time in the study area, with the increase of subgrade height, the slope gradient increases, and the wind speed at the bottom of the subgrade and the bottom of the lee slope decreases, The wind speed at the bottom of the lee slope decreased significantly, resulting in accumulation of snow particles mainly on the windward and leeward slopes, and the snow cover on the leeward slope was more serious, while the snowmelt runoff eroded within the embankment, The height of subgrade is increased and the slope slope is increased. The area of snowmelt erosion increases with the increase of snowmelt mass and soil saturation, Roadbed entire cross-section. The results provide a theoretical basis to quantify the impact of wind and snow snow embankment erosion cold area highway.