| With the construction of high-grade roads in mountainous areas,the roadbeds in the form of high filling and deep excavation are gradually increasing.The filling of high-filled embankments is high,and the amount of engineering is large.It is more likely to cause overall landslide under the influence of its own weight,driving load and environmental factors.For the problem of roadbed instability such as uneven settlement,it is necessary to pay attention to the stability of high fill embankment.The laying of a certain number of geogrids in a high fill embankment can increase the stability of the embankment by virtue of its excellent drawing performance,durability and friction characteristics.Domestic and foreign scholars have carried out related research from the aspects of roadbed form,filling method and reinforcement treatment,but there are still many shortcomings in the study of the stability of reinforced high fill embankment.The engineering practice of reinforced high fill embankment is still Greater than the theoretical height.Therefore,in view of the shortcomings of the current research on the stability of reinforced high-filled embankment,this paper relies on the indoor drawing experiment of ABAQUS finite element multi-factor simulation analysis by the Hebei Provincial Department of Transportation Science and Technology Project.The building analyzes the stability of the high fill embankment.The study has the following results:(1)It is found through the drawing test that the grid type has a great influence on the interface characteristics.The ultimate tensile force of the two-way geogrid with lower tensile strength is larger than that of the one-way geogrid with high tensile strength.The transverse ribs of the geogrid act to end the frictional resistance.The influence of water content on the interface of the reinforced soil is the larger the water content in a certain range,the greater the ultimate tensile force,the better the drawing characteristics when the water content is 20%,the moisture content mainly affects the cohesive force of the cohesive soil,and the interface friction The coefficient has almost no effect.(2)On the field experiment of the typical section of Jingxin Expressway,it is found that the internal stress and strain of the embankment are different.The horizontal displacement and settlement of the middle and lower sections of the embankment are relatively large,and the top displacement is relatively small.It should be fully considered when laying the geogrid.In this regard,appropriately increasing the density of the grid in the lower part of the embankment(below 20 m)can improve the stability of the slope.The long-term observation for eight months shows that the reinforced high-fill embankment settles faster in 90 days,and the settlement begins to slow down within 90d-150 d,after which the consolidation is basically stable.After the geogrid is reinforced,the settlement of the platform is reduced,and the grille receives and diffuses the earth pressure.The results of the high embankment section show that the geogrid effectively improves the stability of the embankment.(3)A finite element simulation was carried out to promote the indoor and on-site experimental results.The simulation results show that the smaller the reinforcement spacing is,the better the stability of the high fill embankment is.The longer the reinforcement is,the better the stability of the embankment is.The influence of the length of the reinforcement on the lateral displacement is greater than the influence on the settlement.The length of the material is 1.0H;the stress and strain distribution of the high embankment of different foundation soils are different.Compared with sand,silty cohesive soil and gravel soil,the embankment of sand foundation is better in stability;the smaller the inclination angle of the slope foundation,the more the embankment Stable;the embankment stability of the stepped foundation is better than that of the slope foundation embankment. |
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