Study On Friction Characteristics Of Axial Pipe-soil Interaction In Soft Clays

Pipelines experience thermal stresses and hence resulting in expansion andextension. The foundation soil constrains the axial deformation of the pipeline whichmakes the pipeline under subsidiary stress when it extends axially. When thesubsidiary stress accumulates to a certain limit, the pipeline will buckle laterally.Axial walking and lateral buckling will make the pipeline strike or even damagewhich can cause huge economic losses. So the study on the axial pipe-soilinteraction of the pipeline is very important.A test chamber with reasonable size is designed for the model test. And vacuumcombined surcharge preloading method is used to make remoulded soil for themodel test. In the preparation of soft clay, new methods have been explored toimprove the uniformity of the soil.The influence of loading rate, soil strength and overlying effective pressure hasbeen studied through the model test. Under displacement control mode, the loaddisplacement curve of axial pipe-soil interaction is recorded. Analysis has been doneto explore the law of axial pipe-soil interaction.Shear parameters of pipe-soil interface and soil-soil interface have beenobtained by the interface shear test. Forecast has been done with α method,β method and finite element analysis. Possible reasons for the differencesbetween the predicted values and experimental values are given in the last.