Site Investigations on the Lateral Movement of Skewed Prestressed Concrete Sleepers (PCS) Subjected to Rail Dynamic Loading

Prestressed concrete sleepers (PCS) are crucial for preserving track stability under dynamic train loads. This study compares the dynamic load behavior of a skewed PCS (placed at a minor angle with one rail seat spacing of 0.67 m instead of the conventional 0.70 m) to a non-skewed PCS. Vibration measurements were taken on an operational Malaysian railway line during commuter train passages (six-coach trains traveling at 30-40 km/h) at a curve track. The Integrated Electronic Piezo-Electric (IEPE) sensor installed on the edges of PCS recorded accelerations in three axes, which were then converted to movement (mm). The lateral movement derived from the skewed sleeper is compared against that from an adjacent normal sleeper. The results show that under identical strain, the skewed PCS has larger lateral movements than the non-skewed PCS. This larger movement indicates that lateral movement (skew) has a stronger influence on load distribution and track compliance. The findings shed light on how non-uniform sleeper placement influences dynamic track response, contributing essential data that is useful for railway maintenance and design in ensuring safety and performance on tracks with uneven sleeper alignment.