A numerical analysis using a finite element program was performed on three structures,these include: Hot Mix Asphalt (HMA) reinforced trackbed (ACRS-1), HMA directsupported trackbed (ACRS-2), and traditional Portland Cement Concrete (PCC) slab track(SlabTrack).Although the comprehensive dynamic responses of ACRS-1 were similar withSlabTrack, HMA layer can positively affect the stress distributions. Especially, thehorizontal stresses indicate that the resilience of ACRS-1 was improved relative toSlabTrack. In addition, HMA reinforced substructure has capacity to recover the residualvertical deformation. At a depth of 2 meters beneath rails, the deformation and verticalacceleration of the three structures were negligible. However, when a depth from 0 to 2meters analyzed the peak values of ACRS-2 were the largest among the three structures.So the effective depth for weakening dynamic loadings is mainly from 0 to 2 metersespecially true at 0.5 meters from this analysis.The results from the analysis show that HMA is a suitable material for railwaysubstructure to enhance resilient performance, improve the stress distribution, weakendynamic loading, and lower the vibration especially at the effective depth of 2 meters.The HMA constructed at the top of the stone subbase layer allows the vertical modulus asmooth transition. In terms of the comprehensive dynamic behaviors, ACRS-1 is betterthan SlabTrack especially from the aspects stated above. The results for ACRS-2 areinconclusive and needs further research.
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