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• Experimentally investigation on ballasted railway tracks' longitudinal resistance and stiffness with standard and advanced Y-shaped steel sleepers. • Determination the shares of various track components in providing longitudinal resistance by measuring the displacement of the track panel. • According to the results, the shares of the rail fasteners and the sleepers in the longitudinal resistance can vary based on the flexibility or rigidity of the track-to-sleeper connection. • A comparison between the longitudinal resistance of these panels with wooden and concrete ones indicated that steel sleepers could provide acceptable levels of longitudinal resistance by requiring less ballast due to their unique geometry. • Higher prestressed force results in higher resistance and stiffness. In this research, we experimentally investigated ballasted railway tracks' longitudinal resistance and stiffness with standard and advanced Y-shaped steel sleepers. We examined the shares of various track components in providing longitudinal resistance by measuring the displacement of the track panel. Moreover, we validated the results via modeling in finite element software. According to the results, the shares of the rail fasteners and the sleepers in the longitudinal resistance can vary based on the flexibility or rigidity of the track-to-sleeper connection. In addition, a comparison between the longitudinal resistance of these panels with wooden and concrete ones indicated that steel sleepers could provide acceptable levels of longitudinal resistance by requiring less ballast due to their unique geometry. Steel sleepers can therefore provide the necessary stability in track sections where we could not utilize other sleepers due to height restrictions. This resistance also depends on the prestressed torque force in the fastener springs. Precisely, higher prestressed-force results in higher resistance and stiffness. Based on the results, we obtained the longitudinal resistance per sleeper in the track panels with standard steel sleepers and Y-shaped sleepers at spring prestressed torque forces of 80 N.m, 60 N.m, and 100 N.m to be about 5.05, 4.55, 7.5, and 11.4 kN/sleeper, respectively. The results of FE models showed a difference of 5.23, 3.55, 2.61, and 2.06 times when applying a vertical load of 300 kN for the longitudinal resistance compared to the condition of no loading. [ABSTRACT FROM AUTHOR]

• Test series were done on different lengths of test panels to understand the track longitudinal behavior along the rail axle. • The 3D finite element model was verified according to the test results. • The sensitivity analysis was done to find the most influential factors in longitudinal resistance and stiffness. • Increasing cohesion from 500 Pa to 2000 Pa increased the TLRF and TLS by 63 %. • This value for the increasing friction angle from 25° to 45° was obtained as 56.5% for TLS and 66.9 for TLRF. A ballasted railway track's longitudinal stiffness and resistance with wooden sleepers were experimentally and numerically investigated. The longitudinal resistance was measured by measuring the force and displacement in the rail's axial direction by increasing the number of sleepers from one to five. The track longitudinal stiffness (TLS) and resistance force (TLRF) of the five-sleeper panel in the experiments were obtained as 15.3 kN/mm and 37.2 kN, respectively. The increased ratio of longitudinal resistance force per sleeper with increasing sleepers' numbers was measured constant. Next, a 3D numerical model was built based on the finite element method, it was verified with test results. TLS and TLRF were reported as 36.75 kN and 15.42 kN/mm in the numerical model. TLS and TLS sensitivity analyses were executed with influential parameters such as ballast property and ballast geometry. The models revealed that vertical load (140 kN) had maximum impact on TLRF with the increasing percentage of 190 %. Finally, two equations were proposed to estimate the variation of TLS/sleeper and TLRF/sleeper with R2 = 0.95 ∼ 0.97. [ABSTRACT FROM AUTHOR]