| With the vigorous development of China’s high-grade highway in the westernregion, the high-filled embankment built more and more and the correspondingnumber of buried pipe culverts across the highway is increasing and the number ofnew culvert structure design type is also emerged, corrugated steel pipe culverts areone of the most representatives of the new structures.High-filled embankment usingcorrugated steel pipe culvert, not only well adapted foundation deformation but alsothe axial and radial load sharing more effectively due to the presence of axialdeformation.That makes full play to the advantages of steel structures.The researchand application of steel corrugated pipe culverts are started relatively late in Chinaespecially under high-filled embankment.There are imperfections research of verticalsoil pressure on top plane of corrugated steel pipe culverts, force and deformationcharacteristics and the theoretical analysis is still immature.First of all, literature reviews about the feature of steel corrugated pipe culvertsunder high-filled embankment in mountainous area at home and abroad arediscussed.Then, relying on in-suit testing in Da-Liu Expressway, uniquecharacteristics of the corrugated steel pipe culverts are under research.Thedistribution of vertical soil pressure above culverts, the force charac ter traits anddeformation characteristics of the surface structure are systematic deeplyresearched.The main progress has been made in the following aspects.1. The deformation characteristics and the force character traits of corrugatedsteel pipe culverts are deeply analysis during construction and operationalphases.Taking K70+610bid section in Da-Liu Expressway as a key test section andselecting a typical cross-section, adhering strain meter in its surface then deformationcharacteristics and the strain of the pipe culverts has gauged.The results showed thatculvert has a good bearing property during construction and operation phases.2. This paper reveals the vertical earth pressure distribution on top plane of thecorrugated steel pipe culverts.First selecting representative sections of pipe culvertsand embedding earth pressure cells in situ tests, then the change law of soil stressdistribution and load regulation of corrugated steel pipe culverts following withheight of filling are observed and analyzed.The results show that vertical earthpressure increases with the height of the fill on the top plane of culverts, but it is always less than the soil column, and that there is earth pressure concentrationphenomenon on the top center area within a certain range.3. Then, based on the measurement results of soil pressure from in situ testingand Marston theory, a more reasonable mechanical model of earth pressure above theculvert has been proposed.A calculation formula of vertical earth pressure has derivedon the basis of appropriate assumptions and the calculation results can better matchthe actual pipe culverts’ stress state.The result shows that soil density has greatinfluence while angle of internal friction and cohesion are affected little. |
