Development and expansion of cities in one hand and increasing transport needs on the other hand have been causing underground constructions. So understanding the behavior of these structures is essential. Ground disp...Development and expansion of cities in one hand and increasing transport needs on the other hand have been causing underground constructions. So understanding the behavior of these structures is essential. Ground displacement around the tunneling area is one of the most important issues which have been studied by many researchers, while the effects of the slope behavior of the ground on the tunnel is paid less attention. This study will have analyzed the effects of frequency and surface slope on the surface subsidence caused by tunneling under dynamic loads (without structure). The results show that the frequency and surface slope have significant effects on the land displacements and the area surrounded by a tunnel.展开更多
In this paper,the process of wind erosion on two kinds of soil from the agro-pastoral area of Inner Mongolia are studied using wind tunnel experiments,considering the wind speed,blown angle of wind and soil moisture c...In this paper,the process of wind erosion on two kinds of soil from the agro-pastoral area of Inner Mongolia are studied using wind tunnel experiments,considering the wind speed,blown angle of wind and soil moisture content.The results showed that the modulus of soil wind erosion increases with an increase of wind speed.When the wind speed exceeds a critical value,the soil wind erosion suddenly increases.The critical speed for both kinds of soil is within the range of 7-8m·s-1.For a constant wind speed,the rate of soil wind erosion changes from increasing to falling at a critical soil slope.The critical slope of loam soil and sandy loam soil is 20° and 10°,respectively.Soil moisture content has a significant effect on wind erosion.Soil wind erosion of both soils decreases with an increase of the soil water content in two treatments,however,for treatment two,the increasing trends of wind erosion for two soils with the falling of soil water content are no significant,especially for the loam soil,and in the same soil water content,the wind erosion of two soils in treatment one is significantly higher than treatment two,this indicates reducing the disturbance of soil surface can evidently control the soil wind erosion.展开更多
文摘Development and expansion of cities in one hand and increasing transport needs on the other hand have been causing underground constructions. So understanding the behavior of these structures is essential. Ground displacement around the tunneling area is one of the most important issues which have been studied by many researchers, while the effects of the slope behavior of the ground on the tunnel is paid less attention. This study will have analyzed the effects of frequency and surface slope on the surface subsidence caused by tunneling under dynamic loads (without structure). The results show that the frequency and surface slope have significant effects on the land displacements and the area surrounded by a tunnel.
基金supported by Key Program of National Natural Science Foundation of China(Grant No. 41130744)China National Natural Science Foundation (Grant No. 40971165)State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau open Foundation(Grant No. 10501-1220)
文摘In this paper,the process of wind erosion on two kinds of soil from the agro-pastoral area of Inner Mongolia are studied using wind tunnel experiments,considering the wind speed,blown angle of wind and soil moisture content.The results showed that the modulus of soil wind erosion increases with an increase of wind speed.When the wind speed exceeds a critical value,the soil wind erosion suddenly increases.The critical speed for both kinds of soil is within the range of 7-8m·s-1.For a constant wind speed,the rate of soil wind erosion changes from increasing to falling at a critical soil slope.The critical slope of loam soil and sandy loam soil is 20° and 10°,respectively.Soil moisture content has a significant effect on wind erosion.Soil wind erosion of both soils decreases with an increase of the soil water content in two treatments,however,for treatment two,the increasing trends of wind erosion for two soils with the falling of soil water content are no significant,especially for the loam soil,and in the same soil water content,the wind erosion of two soils in treatment one is significantly higher than treatment two,this indicates reducing the disturbance of soil surface can evidently control the soil wind erosion.
