A welded bearing plate is a novel structural component for force transmission in prestressed concrete. Its bearing capacity in the anchorage zone is directly related to the overall safety of the prestressed concrete structure. Elastoplastic deformation, damage evolution, and failure mechanisms within the anchorage zone under prestressing loads remain pivotal scientific issues that necessitate in-depth investigation. In this study, a numerical model of the concrete anchorage zone with welded bearing plates is developed with ANSYS software. Comprehensive simulations are carried out to analyze the structural response from initial deformation to ultimate failure under cyclic and vertical displacement loads. The accuracy of the proposed numerical model is verified through a comparative analysis with existing experimental results. Parametric studies are conducted to systematically assess the influence of key design parameters, such as the base plate thickness, flared tube diameter, and wall thickness, on the stress distribution and ultimate load, leading to structural optimization of the bearing plate, which is further validated by physical testing. The results indicate that the plastic-damage microplane model effectively captures the localized compressive behavior and agrees with the experimental observations, thus confirming its feasibility and applicability. In addition, the load-carrying capacity and stress distribution are significantly improved by increasing the base plate and flared tube thickness, with the base plate thickness having a more pronounced effect. Both parameters are generally positively correlated with structural performance. In contrast, variations in the flared tube diameter have a relatively marginal effect. Following structural optimization, the load-transfer performance of the welded bearing plate is superior to that of the original design, particularly in terms of its higher ultimate load capacity and ability to controls cracks control (i.e., delayed initiation and reduced propagation). These findings provide valuable theoretical insights and data support for evaluating load capacity, understanding stress distribution mechanisms, and optimizing the engineering design of concrete anchorage zones.