The use of low embankments is of significant concern for ecological protection in aridoasis areas.Based on the project of Sansha Expressway located in Kashgar City,Xinjiang,China,physical model tests were conducted in...The use of low embankments is of significant concern for ecological protection in aridoasis areas.Based on the project of Sansha Expressway located in Kashgar City,Xinjiang,China,physical model tests were conducted in this study to investigate the dynamic response of the low embankment as per the effects of road structure,load amplitude,load frequency,load cycle,and moisture content.The dynamic stress is shown to increase with load amplitude while the dynamic elastic modulus decreases with load amplitude under short-term loading.The load frequency slightly influences the soil’s dynamic behavior;higher frequencies can improve the dynamic elastic modulus of the subgrade soil.The moisture content has greater influence on the mechanical properties of the subsoil than that of subgrade layer.The subgrade bears the majority of the traffic load as the stress dissipates to 37%of the whole value on its surface.The number of load cycles has the greatest effect on the dynamic response among the influencing factors tested.The dynamic elastic modulus with the type of long-term dynamic loading is only 40%-52%of that with static loading across the entire depth range.The dynamic stress shows significant accumulation with load cycles over the long-term dynamic loading test and becomes stable after 8×10~4 cycles of loading.An equation is established to quantify the cumulative dynamic stress in the low embankment under long-term dynamic loading conditions.展开更多
At present, it is usually used the method that elevating the height of embankment to design passages of freeway to avoid transverse traffic disturbance in plain areas of China. But when design low embankment, it is di...At present, it is usually used the method that elevating the height of embankment to design passages of freeway to avoid transverse traffic disturbance in plain areas of China. But when design low embankment, it is difficulty for drainage or setting passages and culverts. Hengshui to Darning freeway in Hebei provence （Heng-Da freeway） is one section of Dalian to Guangzhnu freeway. This paper analyzes the characteristic of climate, geology, hydrology and low water table, good permeability stratum soil and its little and mass rain fall and deep drinking water well in the plain areas of North China when design low embankment of Heng-Da freeway, puts forward the drainage methods of water collecting filtration system to solve the drainage problem of passages and culverts, aiming at the type and the measures of the pollution on the surface, the channel collection purification infiltration system of highway uses the single composite technology of aerobic and oxygen to digest - precipitation-absorption of artificial materials percolation of soil to deal with the pollution of the rain on the road （the composite technology use the vermiculite as the material of infiltration）, which be controlled in the drinking range of the water standard. It not only efficiently solved the problem of water collected in the channel, but also supplied the groundwater. It has reached the environment-friendly road construction purpose of the sustainable development of highway construction, ＂environment friendly＂ and ＂resource conservation＂.展开更多
基金funded by the National Natural Science Foundation of China(Grant No.41790443)the Fundamental Research Funds for the Central Universities,Chang’an University(CHD)(Grant No.300102218412)。
文摘The use of low embankments is of significant concern for ecological protection in aridoasis areas.Based on the project of Sansha Expressway located in Kashgar City,Xinjiang,China,physical model tests were conducted in this study to investigate the dynamic response of the low embankment as per the effects of road structure,load amplitude,load frequency,load cycle,and moisture content.The dynamic stress is shown to increase with load amplitude while the dynamic elastic modulus decreases with load amplitude under short-term loading.The load frequency slightly influences the soil’s dynamic behavior;higher frequencies can improve the dynamic elastic modulus of the subgrade soil.The moisture content has greater influence on the mechanical properties of the subsoil than that of subgrade layer.The subgrade bears the majority of the traffic load as the stress dissipates to 37%of the whole value on its surface.The number of load cycles has the greatest effect on the dynamic response among the influencing factors tested.The dynamic elastic modulus with the type of long-term dynamic loading is only 40%-52%of that with static loading across the entire depth range.The dynamic stress shows significant accumulation with load cycles over the long-term dynamic loading test and becomes stable after 8×10~4 cycles of loading.An equation is established to quantify the cumulative dynamic stress in the low embankment under long-term dynamic loading conditions.
文摘At present, it is usually used the method that elevating the height of embankment to design passages of freeway to avoid transverse traffic disturbance in plain areas of China. But when design low embankment, it is difficulty for drainage or setting passages and culverts. Hengshui to Darning freeway in Hebei provence （Heng-Da freeway） is one section of Dalian to Guangzhnu freeway. This paper analyzes the characteristic of climate, geology, hydrology and low water table, good permeability stratum soil and its little and mass rain fall and deep drinking water well in the plain areas of North China when design low embankment of Heng-Da freeway, puts forward the drainage methods of water collecting filtration system to solve the drainage problem of passages and culverts, aiming at the type and the measures of the pollution on the surface, the channel collection purification infiltration system of highway uses the single composite technology of aerobic and oxygen to digest - precipitation-absorption of artificial materials percolation of soil to deal with the pollution of the rain on the road （the composite technology use the vermiculite as the material of infiltration）, which be controlled in the drinking range of the water standard. It not only efficiently solved the problem of water collected in the channel, but also supplied the groundwater. It has reached the environment-friendly road construction purpose of the sustainable development of highway construction, ＂environment friendly＂ and ＂resource conservation＂.
