# Response of Corroded Steel Pipeline Without and with CFRP Reinforcement to Reverse Fault Movement
###### Abstract  
Corroded steel pipelines are particularly vulnerable to failure due to ground movement, which highlights the need to improve their seismic resistance through reinforcement methods. This paper establishes a three-dimensional finite element model of a corroded steel pipeline subjected to a reverse fault, which considers the effects of the corrosion position and depth, winding thickness, and length of carbon fiber-reinforced polymer (CFRP), to investigate the stress, strain, elliptic deformation, and failure modes of the pipeline before and after CFRP reinforcement. Results indicate that the main failure mode of the intact and corroded pipeline crossing the reverse fault is local buckling. Corrosion intensifies the response of the cross-fault pipeline, accelerates its failure occurrence, and promotes transformation from a single failure mode to multiple failure modes. For CFRP reinforcement, an increase in CFRP winding thickness can effectively inhibit the growth of the pipeline's compressive strain, thus reducing the buckling potential. Each additional CFRP layer can further enhance the overall buckling resistance but at a decreasing rate. Similarly, longer CFRP winding improves buckling resistance though the effectiveness per meter decreases. Therefore, it is recommended that the thickness and length of CFRP winding on the pipeline should be optimized to obtain the best reinforcement at a reasonable cost. corroded pipeline; reverse fault; CFRP reinforcement; mechanical response; failure mode IEEEexample:BSTcontrol  
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[PERSON], [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON] Response of Corroded Steel Pipeline Without and with CFRP Reinforcement to Reverse Fault Movement. 1  
[PERSON], [PERSON]. losses [11]. Most studies on corroded pipelines mainly focus on failure modes under simple loads like internal pressure [12]. However, there is limited research on the damage amplification effects and failure modes of corrosion in hanging wall and football pipelines subjected to faults. Research on the performance analysis methods and model prediction of buried corroded pipelines has gradually become a key point in pipeline engineering research. Researchers have carried out a large amount of work on the modeling, simulation, and prediction of pipeline corrosion characteristics. [PERSON] et al. [13] proposed a nonuniform corrosion field modeling method based on the random field theory to simulate the complex corrosion morphology on the outer wall of the pipeline and, combined with finite element analysis, predict the pipeline burst bearing capacity. In addition, for the corrosion defect behavior of high-strength steel pipes, [PERSON] et al. [14] used the extended finite element method and artificial neural network to analyze the stress field change and rupture behavior at the crack tip, further improving the adaptability and accuracy of steel pipe corrosion prediction. [PERSON] et al. [15] evaluated the seismic resilience of urban water supply networks considering the soil corrosion environment and the service age of pipelines. The results showed that different corrosion environments and service ages would significantly affect the seismic resilience of the pipelines. In summary, the research on the performance analysis and model prediction of buried corroded pipelines has made significant progress in aspects such as nonuniform corrosion field modeling and machine learning-based prediction methods. There are numerous studies on the reinforcement of buried pipelines subject to fault-induced PGD, such as selecting higher-grade steel, reducing the pipeline diameter-to-thickness ratio or buried depth, and setting flexible joints between pipeline segments. Other solutions have also been considered, including increasing the width of the backfill trench and reducing the pipeline-ground friction. Retrofitting corroded steel pipeline CFRP materials has been proposed, owing to many features including lightweight, high tensile strength, and high flexibility for application in complex terrains and irregular pipeline shapes.