Transition zones in railway track networks are locations that suffer from the considerable changes in track support structures which result in the abrupt change in track stiffness furthermore causing severe damage to the railway track system. Hence, this study aims to develop a novel flowable soil as backfill material for railway bridge approach which resolves the sudden change in track stiffness at these transition zones, thereby enhancing the service life of the whole track system. To further justify the economical and practical advantages of this new backfill material, two mixture-types of flowable soil are created using locally available resources: silty soil and clayey soil. Evaluation of the behavior of these two mixture-types is done through the flowability, setting-time, unconfined compressive strength, and freeze–thaw cycle tests. Numerical simulation is then employed to investigate the performance of flowable soil as a backfill material for railway bridge approach under repeated loads from trains in mitigating the severe vibration. The findings reveal that the engineering properties of the silty soil mixtures outperform that of the clayey soil mixtures, especially in terms of their strength and durability. Based on the experiment and simulation results, flowable soil is promising to be applied as sustainable backfill material of the railway bridge approach. The lightweight and proper resilience modulus of this material are confirmed to release the burden on track foundation and thereby, improving the track stiffness at bridge end under dynamic train loads.

铁路轨道网络中的过渡区是轨道支撑结构发生重大变化的位置，这会导致轨道刚度的突然变化，进而对铁路轨道系统造成严重破坏。因此，本研究旨在开发一种新型的可流动土壤作为铁路桥梁方法的回填材料，以解决这些过渡区域的轨道刚度突然变化，从而延长整个轨道系统的使用寿命。为了进一步证明这种新型回填材料的经济和实用优势，利用当地可利用的资源创建了两种混合类型的可流动土壤：粉质土壤和黏土。通过流动性，凝固时间，无侧限抗压强度和冻融循环试验对这两种混合物类型的性能进行评估。然后，通过数值模拟研究了在火车反复施加的载荷下，可缓解流动性的土壤作为铁路桥梁方法的回填材料的性能，以减轻剧烈的振动。研究结果表明，粉质土混合物的工程性能优于粘质土混合物，特别是在强度和耐久性方面。根据试验和模拟结果，可流动的土壤有望被用作铁路桥梁方法的可持续回填材料。证实了这种材料的轻质性和适当的回弹模量，可以减轻轨道基础的负担，从而改善动态列车荷载下桥头处的轨道刚度。