CIPP修复内衬-埋地柔性管道复合结构受力特性数值模拟研究OA

Flexible pipelines are widely used in underground pipeline engineering.With the increase of service life,a large number of flexible pipelines are urgently needed to be repaired.Curied in place pipe(CIPP)is a commonly non excavation pipeline repair technique.In order to study the mechanical characteristics of liner-buried flexible pipeline composite structure by CIPP repair,a 2D finite element model of soil-buried flexible pipeline-lining inter-action was constructed.The reliability of the model was verified by comparing with the results of soil box model tests.The influence of lining elastic modulus,lining wall thickness,soil density around the pipe and initial ellipticity on the CIPP repair was discussed by parameter sensitivity analysis.The research results indicate that the maximum strain of the lining occurs at a position with about 65 °from both sides of the sample to the top of the pipe,and the strain at the top of the pipe is greater than that at the bottom;The local strain peak at the dangerous point of the lin-ing increases with the decrease of the elastic modulus,while the overall stress-strain of the lining decreases accord-ingly;The compactness of the soil around the pipe is positively correlated with the bearing capacity of the composite structure,and the dangerous points of the lining move towards the top of the pipe with the compactness decreases of the soil around the pipe;With the initial ellipticity of the buried flexible pipeline increases,the stiffness of the composite structure decreases,and the peak strain increases at the dangerous point.The research results can pro-vide reference for CIPP repair design.