In a conventional railway system, timber sleepers have been widely used for ballasted railway tracks to carry passengers and transport goods. However, due to the limited availability of reliable and high-quality timbers, and restrictions on deforestation, the “interspersed” approach is adopted to replace ageing timbers with concrete sleepers. The replacement of ageing timber sleepers is frequently done over old and soft existing formations, which have been in service for so long, by installing new stiff concrete sleepers in their place. This method provides a cost-effective and quick solution for the second and third track classes to maintain track quality. Presently, railway track buckling, caused by extreme temperature, is a serious issue that causes a huge loss of assets in railway systems. The increase in rail temperature can induce a compression force in the continuous welded rail (CWR) and this may cause track buckling when the compression force reaches the buckling strength. According to the buckling evidences seen around the world, buckling usually occurs in ballasted track with timber sleepers and thus there is a clear need to improve the buckling resistance of railway tracks. However, the buckling of interspersed tracks has not been fully studied. This unprecedented study highlights 3D finite element modelling of interspersed railway tracks subjected to temperature change. The effect of the boundary conditions on the buckling shape is investigated. The results show that the interspersed approach may reduce the likelihood of track buckling. The results can be used to predict the buckling temperature and to inspect the conditions of interspersed railway tracks. The new findings highlight the buckling phenomena of interspersed railway tracks, which are usually adopted during railway transformations from timber to concrete sleepered tracks in real-life practices globally. The insight into interspersed railway tracks derived from this study will underpin the life cycle design, maintenance, and construction strategies related to the use of concrete sleepers as spot replacement sleepers in ageing railway track systems.

在传统的铁路系统中，木材轨枕已被广泛用于压载铁路轨道，以运送旅客和运输货物。但是，由于可靠和高质量木材的供应有限，以及对森林砍伐的限制，因此采用“散布”的方法用混凝土轨枕代替陈旧的木材。老化的木轨枕的更换通常是在已经使用了很长时间的旧的和软的现有地层上进行的，方法是在其位置上安装新的刚性混凝土轨枕。该方法为第二和第三轨道类提供了一种经济高效的快速解决方案，以保持轨道质量。当前，由极端温度引起的铁路轨道弯曲是一个严重的问题，其导致铁路系统中资产的巨大损失。钢轨温度的升高会在连续焊接钢轨（CWR）中产生压缩力，当压缩力达到屈曲强度时，这可能会引起轨道屈曲。根据全世界屈曲的证据，屈曲通常发生在带有木轨枕的压载轨道中，因此显然需要提高铁路轨道的屈曲抵抗力。但是，散布轨道的屈曲尚未得到充分研究。这项史无前例的研究突显了温度变化对穿插式铁路轨道的3D有限元建模。研究了边界条件对屈曲形状的影响。结果表明，散布的方法可以减少轨道弯曲的可能性。结果可用于预测屈曲温度并检查散布的铁路轨道的状况。新发现强调了散布在铁轨上的屈曲现象，这种现象通常在全球范围内的现实生活中，从木材到混凝土轨枕的铁路转换过程中普遍采用。从这项研究中得出的穿插式铁路轨道的洞察力将支持生命周期的设计，维护和施工策略，这些策略与在老化的铁路系统中使用混凝土轨枕作为现场更换轨枕有关。