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• The measurement data is used to validate the pantograph-catenary model in overlap sections. • Strong dependence on interaction performance of the speed with crossing point height is observed. • Steady arm damper improves the trailing pantograph's performance but sacrifice the leading one's. The overlap section is a railway catenary arrangement where the pantograph transfers from one section to another. In the overlap section, the unsynchronised vibration of two contact wires, contact wire height variation, and elasticity unevenness destabilise the pantograph-interaction performance. This paper presents a systematic investigation of the dynamic behaviours of the pantograph-catenary in an overlap section, including the mathematical modeling, model validation and numerical analysis. In combination with the traditional shape-finding method, an initialization procedure is proposed to accurately describe the crossing point height in an overlap section of a catenary. The measurement data of the maximum uplift of the crossing point collected from the field test in the Gardemobanen line is utilised to validate the pantograph-catenary model in the overlap section. The numerical analysis mainly focuses on the effect of the crossing point height and the inclusion of steady arm damping on the interaction performance at different speeds. The results indicate a strong dependence of the dynamic behaviour in an overlap section on the train speed. A good performance can be achieved with a low crossing point when the speed is much lower than the design speed, while a high crossing point can benefit the transition distance and maximum contact force at high speed. The inclusion of a steady arm damper can improve the pantographs' performance at a low speed. However, the effectiveness degrades with the increase of the train speed, especially for the leading pantograph. [ABSTRACT FROM AUTHOR]

• A damping identification of railway catenary systems is presented. • A camera system measures a full-span uplift of an existing catenary span. • A pinhole camera model for scale-factor estimation purposes is described. • Sixty-nine train passages are acquired for statistical analysis of uplift and damping. • Recommended Rayleigh damping coefficients for numerical models are proposed. For electrified railways, the catenary dynamic behavior is critical to ensure a robust and steady current collection quality for electric trains. The current collection is achieved as the catenary directly interacts with the pantograph, installed on the car-body roof to provide an electrical current to the engine. Damping plays an essential role in numerical simulations of pantograph-catenary interaction, especially for multiple pantographs. However, damping estimation of existing catenary sections is recognised as a challenge, and only a few studies have been published with single values of damping estimations. This study aimed to estimate the spatially distributed damping of an existing catenary span through full-span uplift measurements using a vision-based line-tracking system (VIBLITE). A detailed study was performed at critical locations along the catenary span. Sixty-nine single/double-pantograph train passages were acquired during scheduled train operation. Time series of uplift and acceleration were obtained through a line-tracking image-processing technique. The uplift amplitude was statistically analysed, where the damping ratios were identified using the covariance-driven stochastic subspace identification (Cov-SSI) method. Finally, the spatially distributed Rayleigh damping coefficients were successfully identified to quantify the important spatial variation in energy dissipation within a span. Arithmetic averages of damping coefficients over all measuring locations were obtained and recommended for future numerical simulations. [ABSTRACT FROM AUTHOR]