To investigate the distinctive characteristics of deformation and internal force variations in frame beam anchor structure supporting frozen soil slopes during freezing-induced frost heave, a comprehensive three-dimensional finite element model was developed. This model, utilizing the Winkler elastic foundation beam theory, is engineered to examine frost heave occurrences in frame anchor structures during freezing periods. The frame beam is modeled as a homogeneous elastic Euler-Bernoulli continuous beam, while the frozen soil behind the slope is represented through simplified pre-compressed soil springs. Simultaneously, based on the heat conduction differential equation during the phase coexistence of solid and liquid in the freezing-expansion process, the freezing expansion distribution force acting on the frame beam is obtained. By employing MATLAB programming and leveraging existing engineering cases, customized calculation programs were developed and compared against numerical simulation outcomes. The findings underscore the efficacy of the proposed method in accurately portraying the free frost heave displacement of frozen soil on slopes. Lateral displacements and bending moments obtained through this approach are consistently aligned with the results of numerical simulations. Moreover, the proposed calculation method offers a swift means of assessing frost heave displacement and the stress state of frame anchor structures, requiring only a minimal set of parameters. The research outcomes not only present a comprehensive insight into the three-dimensional dynamics between frozen soil and frame anchor support structures but also provide invaluable scientific guidance for designing frame anchor slope structures in cold regions.