Experimental an‎d numerical study of shoulder ballast effects on railway track lateral resistance

9/7/2026 12:00:00 AM

The increase in railway track speed has been made possible by welding the rails an‎d adopting the Continuous Welded Rail (CWR) method. Experimental tests an‎d numerical modeling have shown that the design an‎d geometry of the sleeper, as well as the geometry of the ballast an‎d its regions (shoulder an‎d crib), significantly influence the lateral resistance of the railway track. The primary objective of these experiments an‎d simulations is to enhance track stability an‎d lateral resistance. In this thesis, three types of sleepers (B70, winged-center, an‎d winged sleepers) an‎d different ballast shoulder heights (0%, 50%, an‎d 100%) were investigated using a track panel consisting of seven sleepers. The Single Tie Push Test (STPT) was performed, followed by numerical modeling in ABAQUS. In each panel, three sleepers were modeled. The STPT results showed that the winged sleeper achieved the highest lateral resistance at 2 mm displacement an‎d 100% ballast shoulder height, demonstrating an 80% higher resistance compared to the B70 sleeper an‎d a 50% higher resistance compared to the winged-center sleeper. Furthermore, numerical modeling using the Finite Element Method (FEM) was carried out to validate an‎d compare the experimental results. In the numerical models, each panel contained three sleepers, with B70 sleepers spaced 60 cm apart, an‎d winged-center an‎d winged sleepers spaced 63.5 cm apart. For the B70 sleeper, the differences between experimental an‎d numerical lateral resistance at ballast shoulder heights of 0%, 50%, an‎d 100% were 16%, 0.5%, an‎d 1%, respectively. For the winged-center sleeper, the differences were 2.6%, 4.3%, an‎d 2%, while for the winged sleeper, they were 1.4%, 6%, an‎d 1%, respectively. Finally, a sensitivity analysis of the ballast’s mechanical properties indicated that, for cohesion (C), the final lateral resistance increased by 33% for the B70 sleeper, 53% for the winged-center sleeper, an‎d 62% for the winged sleeper. For the friction angle (ϕ), the increases were 14%, 55%, an‎d 47%, respectively. For the modulus of elasticity (E), the increases were 1.3%, 27%, an‎d 1.8%, respectively. Thus, cohesion (C) was identified as the most influential parameter for enhancing the lateral resistance of the panels.

: مقاومت جانبي، خط با جوشكاري پيوسته (CWR)، آزمايش فشاري تراورس منفرد (STPT)، تراورس B70، تراورس ميان‌بال، تراورس بالدار، ABAQUS، FEM

Lateral Resistance, Continuous Welded Rail (CWR), Single Tie Push Test (STPT), B70 Sleeper, Winged-Center Sleeper, Winged Sleeper, ABAQUS, Finite Element Method (FEM)

Mehraein Talebi Kahangi

Jabbar Ali Zakeri & Seyyed Ali Mosayebi