RESEARCH ON PIPELINE DEFORMATION IN PERMAFROST REGION USING INVERSE FINITE ELEMENT METHOD BASED ON IBEAM3 ELEMENT

Combined with strain-shape algorithm, shape sensing technology is able to achieve the mapping of the strain of measured points and their spatial position. This technology can truly reflect the spatial attitudes and shape changes of the objects to be measured, and can realize dynamic real-time monitoring. An inverse finite element method based on iBeam3 element is proposed to realize real-time monitoring of pipeline deformation in this paper. The theoretical framework model of inverse finite element method based on iBeam3 element is established; The rationality of this model is verified by experiments; The pipeline deformation test is designed in the permafrost area and the inverse finite element analysis model is established based on the surface strain information measured by the strain sensor; The reconstruction of the pipe shape in the whole freeze-thaw cycle is realized. The test results show that the method can not only monitor the complete deformation process of pipeline with freeze-thaw cycle in real time, but also ensure the accuracy. It has great potential in solving the health monitoring problem of pipeline structure in cold areas.