Finite Element Analysis of Mechanical Behavior of Steel Reinforced Concrete (SRC) Columns Designed by Different Methods

The design of integrated station-bridge structures is challenged by the coexistence of building codes based on Limit State Design (LSD) and railway codes using Allowable Stress Design (ASD). This study employs finite element analysis to compare the performance of Steel Reinforced Concrete (SRC) columns designed under these two philosophies. The results demonstrate the significant conservatism of the ASD method: When achieving the same safety margin, the ASD-designed column required 2.36 times the cross-sectional area, yielding an 89% higher axial capacity but a disproportionately small increase in shear strength, indicating material inefficiency. A subsequent parametric analysis identified steel strength as key to axial capacity and concrete strength as critical for shear capacity, with shear performance reaching its maximum at an axial compression ratio of 0.6. These findings quantify these behavioral differences, offering a basis for refining design methods and codes harmonization for such structural members.