The interaction between geogrid and soil is crucial for the stability of geogrid-reinforced earth structure. In finite element (FE) analysis, geogrids are usually assumed as beam or truss elements, and the interacti...The interaction between geogrid and soil is crucial for the stability of geogrid-reinforced earth structure. In finite element (FE) analysis, geogrids are usually assumed as beam or truss elements, and the interaction between geogrid and soil is considered as Coulomb friction resistance, which cannot reflect the true stress and displacement developed in the reinlbrcement. And the traditional Lagrangian elements used to simulate soil always become highly distorted and lose accuracy in high-stress blocks. An improved geogrid model that can produce shear resistance and passive resistance and a soil model using the Eulerian technique, in combination with the coupled Eulerian-Lagrangian (CEL) method, are used to analyze the interaction between geogrid and soil of reinforced foundation test in ABAQUS. The stress in the backfill, resistance of geogrid, and settlement of foundation were computed and the results of analysis agree well with the experimental results. This simulation method is of referential value for FE analysis of reinforced earth structure.展开更多
In order to consider the influence of steel pole on the measurement of wind speed sensors and determinate the installation position of wind speed sensors, the flow field around wind speed sensors was investigated. Bas...In order to consider the influence of steel pole on the measurement of wind speed sensors and determinate the installation position of wind speed sensors, the flow field around wind speed sensors was investigated. Based on the three-dimensional steady Reynolds-averaged Navier-Stokes equations and k-ε double equations turbulent model, the field flow around the wind speed sensor and the steel pole along a high-speed railway was simulated on an unstructured grid. The grid-independent validation was conducted and the accuracy of the present numerical simulation method was validated by experiments and simulations carried out by previous researchers. Results show that the steel pole has a significant influence on the measurement results of wind speed sensors. As the distance between two wind speed sensors is varied from 0.3 to 1.0 m, the impact angles are less than ±20°, it is proposed that the distance between two wind speed sensors is 0.8 m at least, and the interval between wind speed sensors and the steel pole is more than 1.0 m with the sensors located on the upstream side.展开更多
基金Supported by National Natural Science Foundation of China (No. 50678032)
文摘The interaction between geogrid and soil is crucial for the stability of geogrid-reinforced earth structure. In finite element (FE) analysis, geogrids are usually assumed as beam or truss elements, and the interaction between geogrid and soil is considered as Coulomb friction resistance, which cannot reflect the true stress and displacement developed in the reinlbrcement. And the traditional Lagrangian elements used to simulate soil always become highly distorted and lose accuracy in high-stress blocks. An improved geogrid model that can produce shear resistance and passive resistance and a soil model using the Eulerian technique, in combination with the coupled Eulerian-Lagrangian (CEL) method, are used to analyze the interaction between geogrid and soil of reinforced foundation test in ABAQUS. The stress in the backfill, resistance of geogrid, and settlement of foundation were computed and the results of analysis agree well with the experimental results. This simulation method is of referential value for FE analysis of reinforced earth structure.
基金Projects(U1334205,51205418)supported by the National Natural Science Foundation of ChinaProject(2014T002-A)supported by the Science and Technology Research Program of China Railway CorporationProject(132014)supported by the Fok Ying Tong Education Foundation of China
文摘In order to consider the influence of steel pole on the measurement of wind speed sensors and determinate the installation position of wind speed sensors, the flow field around wind speed sensors was investigated. Based on the three-dimensional steady Reynolds-averaged Navier-Stokes equations and k-ε double equations turbulent model, the field flow around the wind speed sensor and the steel pole along a high-speed railway was simulated on an unstructured grid. The grid-independent validation was conducted and the accuracy of the present numerical simulation method was validated by experiments and simulations carried out by previous researchers. Results show that the steel pole has a significant influence on the measurement results of wind speed sensors. As the distance between two wind speed sensors is varied from 0.3 to 1.0 m, the impact angles are less than ±20°, it is proposed that the distance between two wind speed sensors is 0.8 m at least, and the interval between wind speed sensors and the steel pole is more than 1.0 m with the sensors located on the upstream side.