Research On Reducing-load Measurement And Optimization Design Of The High Fill Culvert

With the rapid development of the transportation industry in our country, coverage area ofthe highway network is more and more widely. High fill culvert application is very wide in theprocess of the construction of high-grade highway in the mountains, But due to the earthpressure calculation theory of the high fill culvert is imperfection, Soil pressure calculationformula and the standard drawing in the bridge opening specification is not suitable for high fillculvert, Caused the calculation of earth pressure numerical differences with the actual situationwhen designing high fill culvert. High fill culvert which have been built, there are somequestions, for example, many diseases, high cost, difficult maintenance and so on. This situationis a serious threat to the normal and safe use of our country’s highway.Based on the above issues, Using large-scale finite element software ANSYS to simulatethe stress conditions and its variation law of the culvert roof which Yitong Kaiyuan highwayLianchang to wulongling (provincial boundary) bid section of the fourth K121+371.41in1-3x2.5high fill reinforced concrete box culvert when laid polystyrene foam board before andafter. Evaluate the lightening effect of polystyrene foam board from three aspects such as thevertical earth pressure, the lateral earth pressure, and the filling culvert roof subsidence.Optimize the culvert design through combining with the soil pressure values obtained by thefinite element numerical simulation, compared with the project cost of the reinforced concretebox culvert that before and after the lightening, finally get the following conclusions:First of all, the vertical earth pressure of the high fill reinforced concrete box culvert isgreater than that calculated by "soil column method" which is in bridge opening specification.Increasing with the filling height, the value of soil pressure increased with nonlinear growth.Stress concentration is gradually weakened increasing with the increase of filling height.Secondly, lightening effect is very obvious by the method of laying polystyrene foamboard on top of the reinforced concrete box culvert, the vertical earth pressure, lateral earthpressure and settlement deformation of soil decrease obviously after lightening. Finally, combined with the value of earth pressure on top culvert after lightening whichgetting by ANSYS numerical simulation, to optimal design of reinforced concrete box culvert.Through the comparison of the project cost we can find that the cost of high fill culvert can begreatly reduced by laying polystyrene foam board.