Numerical simulation studies on wind erosion damage for desert subgrade in sandstorm environment

Applying gas-solid two-phase flow of the Fluent, using k-Ε turbulence model, we could research the wind erosion and failure pattern of the desert roadbed. After analyzing the sand process that includes disturbance slowing, growth recovery for the different cross-sections of the sand subgrade, the weakened and restore area that result from the existence of the sand roadbed as obstacles, we can summarize the regular pattern of the wind change for the feature point section of the roadbed. Through comparing the data, both on-site test data and simulated data have good uniformity. Research results show that under different roadbed cross-sections the distribution of the weakened and restored area is highly sensitive to the changes of different roadbed height and smaller influence on the slope gradient. The different slope gradient along the road winds is obviously different from all kind of height and roadbed cross-sections. When the slope gradient is fixed, with the increase of roadbed height the flow disturbances is enhanced significantly around the roadbed and the wind speed of windward slopes increases obviously on the top and the wind speed of wind slope dropped significantly near the bottom. The height of the subgrade is certain: the smaller the slope is, the gentler the wind along the road changes. The slope gradient of 1/3 shows: when the embankment height increased to 3 m by 1 m, the wind speed on the top increase 12% and the wind speed of wind slope reduces 20% near the bottom. In order to avoid the wind erosion damage of desert roadbed, we suggest that the height of the roadbed should not be too tall and the smaller slope gradient is advisable.