Research on the Mechanism of Load Transfer Structures in the Construction Process of “Internal Support—Large Block” Prefabricated Subway Stations

In the context of rising global temperatures, countries around the world are increasingly tailoring their own “carbon neutrality” plans. China has also formulated its “dual-carbon” goals, and the construction industry is gradually transitioning towards prefabrication to reduce carbon emissions. This paper uses the Sha Pu Station of Shenzhen’s Metro Line 12 as a case study by which to explore the effects and mechanisms of the load transfer structure during the assembly process of prefabricated subway stations. A three-dimensional finite element model considering soil–structure interaction was established using MIDAS GTS NX finite element software, 2018 version. The internal forces, stresses, and deformations of the station structure were compared under two scenarios—with and without the load transfer structure—using a control variable method. The research results indicate that the load transfer structure effectively reduces shear forces, bending moments, and stresses in the station structure; limits lateral displacements during the assembly process; and effectively concentrates the maximum stresses during construction at the location of the load transfer structure, thereby preventing stress concentration phenomena and enhancing the overall stability of the station structure. This study elucidates the role and effectiveness of the load transfer structure during the assembly of prefabricated components in subway stations, providing a reference for the construction of similar prefabricated metro stations.