Geotextile have garnered significant attention for their potential to alleviate pressure on soils and buried structural objects. The behavior of corrugated steel culverts (CSCs) during construction is strongly influenced by the interaction between soil and reinforcement materials. Despite the proven benefits of geosynthetic reinforcement in mitigating deformation and improving structural stability, their influence on CSC behavior when placed at various locations above the culvert crown and the determination of optimal placement remain underexplored. This study analyzes a CSC with a span of 3.55 m, a clear height of 1.42 m, and a soil cover of 0.6 m, constructed from corrugated steel plates with dimensions of 150 × 50 × 5 mm. Experimentally validated numerical simulations using the ZSoil finite element program evaluated vertical displacement and deformation patterns under varying reinforcement configurations during the construction phase. The maximum reduction of 29% occurs when the textile is placed at a shallower depth above the culvert crown. A double-layer reinforcement configuration further enhances performance, reducing vertical displacement by 48.5% compared to the unreinforced structure. These findings underscore the effectiveness of geosynthetic reinforcement in improving CSC performance during construction and offer practical recommendations for optimizing structural design and resilience.