This paper presents an analysis of loaded freight wagon dynamics in curve alignments. We investigate the effects of the combined centre of gravity (CCOG) on the running safety of freight wagons and examine proper position of the CCOG. A simple wagon-rail model is implemented using the multibody dynamics software ADAMS/Rail. The simulation model is operated on curve tracks with various radii and velocities and the curving performances are evaluated. The results indicate that the CCOG can be located within a flexible and accurate range. The longitudinal offset is good for the curving performance and the permissible lateral offset should be assessed based on the curve radius and cant deficiency.

Due to super elevation and centrifugal force, close attention is needed to lateral stability of cargo when the train negotiates curves. To guarantee the security of cargo on wagons, proper blocking, bracing and lashing are essential. In this study, we implement a cargo–wagon–rail coupling model that adopts diagonal lashing to restrain cargo movement. A preliminary dynamic simulation analysis demonstrates that the selected cargo tilts when the wagon negotiates curves. The quasi-static analysis reveals the cargo force condition and the key role of lashing stiffness. Coupling models are endowed with various lashing stiffness values. The curving performance of each model is evaluated considering different running conditions. The results indicate that increasing lashing stiffness reduces lateral cargo vibration and increases lashing tension force until the stable state. The cargo movement in this study is proved to have no significant effect on the wheel–rail interaction. Based on simulation results, this paper determines the diagonal lashing. It is demonstrated that the use of dynamic simulation to calculate the diagonal lashing force will improve cargo stability and avoid unnecessary expenditure on load restraint assemblies. Finally, it is proved that the promotion of pre-tension force is not necessary for diagonal lashings.

The escalating environmental noise pollution along urban rail transit corridors, exacerbated by rapid urbanization, necessitates innovative and efficient noise control measures. A comprehensive investigation was conducted that utilized field measurements of train passing-by noise to establish a statistical energy analysis model for evaluating the acoustic performance of both vertical (VB) and fully enclosed (FB) barrier configurations. The study incorporated Maa’s theory of micro-perforated plate (MPP) parameter optimization and developed a neural network surrogate model focused on insertion loss maximization for barrier geometric design. Key findings revealed significant barrier-induced near-track noise amplification, with peak effects observed at the point located 1 m from the barrier and 2 m above the rail. Frequency-dependent analysis demonstrated a characteristic rise-and-fall reflection pattern, showing maximum amplifications of 1.47 dB for VB and 4.13 dB for FB within the 400–2000 Hz range. The implementation of optimized MPPs was found to effectively eliminate the near-field noise amplification effects, achieving sound pressure level reductions of 4–8 dB at acoustically sensitive locations. Furthermore, the high-precision surrogate model (R² = 0.9094, MSE = 0.8711) facilitated optimal geometric design solutions. The synergistic combination of MPP absorption characteristics and geometric optimization resulted in substantially enhanced barrier performance, offering practical solutions for urban rail noise mitigation strategies.