Abstract: The sequential soil backfilling process can lead to longitudinal uneven settlement in prefabricated struc? tures. However, existing longitudinal deformation models often neglect the deformation of prefabricated linings caused by foundation settlement. To address this, an optimized longitudinal deformation model for prefabricated subway stations is established based on an improved Timoshenko beam model on a Kerr foundation, considering foundation settlement and soil shear effects. The model is validated through comparisons with field measurements. The study shows that, compared to theoretical results from the Euler-Winkler model and the Timoshenko-Pasternak model, the proposed method not only ensures calculation accuracy but also reveals the characteristics of longitudinal deformation induced by foundation settlement. The method effectively captures the trend of vertical settlement at monitoring rings, with predicted longitudinal settlement values showing good agreement with measured data, having an error of only 0.3%. Under the combined effects of overburden load and foundation settlement, buckling occurs in the prefabricated structure, forming a new stable structure, which explains the discontinuous deformation between rings and joints in prefabricated structures.