Sensitivity and reliability analysis for track structures based on probability statistics

This study integrates field-measured train load and temperature load data into the sensitivity and reliability analysis framework of the slab track, thereby overcoming the limitations of existing studies that use fixed load values from design codes. It is found that the sensitivity distribution characteristics of the load effects of the track slab, self-compacting concrete (SCC), and concrete base show a strong regularity. All the findings indicate that the structural thickness has the greatest influence on the load effects, followed by the elastic modulus, while the density has a negligible influence. The influence of the track slab, SCC, and concrete base on the structural load effect exhibits a gradient from top to bottom, with cumulative sensitivity factor totals of 5.216, 5.153, and 0.639, respectively. Enhancing the thickness of the track slab can effectively increase its longitudinal tensile reliability. With thicknesses of 0.3 m or 0.4 m, the track slab is capable of satisfying the design life requirements. This study can provide theoretical underpinnings for the long-life design of track structures.