DYNAMICS OF APPLICATION AND COMPARATIVE ASSESS-MENT OF INTERMEDIATE RAIL FASTENING SYSTEMS ON RE-INFORCED-CONCRETE SLEEPERS OF THE JSC «NC KAZAKHSTAN TEMIR ZHOLY» NETWORK

Abstract

This article presents a comparative analysis of the distribution of intermediate rail fastening systems installed on reinforced-concrete sleepers across the JSC «NC Kazakhstan Temir Zholy» (JSC «NC KTZ») network, based on operational statistics for 2017 and 2025. Four principal fastening system groups were examined: the KB-65 fastening system, clip-based SKL, GK1 systems, ZhBR-65/ZhBR-65Sh fastening systems, and the KPP-5 anchor-type fastening system. The methodology included a comparative assessment of track lengths by fastening type, a synthesis of technical and regulatory characteristics, and an analytical calculation of longitudinal resistance to rail creep and the rail "breathing" zone for CWR track with KB-65 and SKL, GK1 systems. Between 2017 and 2025, the share of SKL, GK1 systems increased from 22.9% to 53.3% (+5,907.84 km), whereas the share of KB-65 systems decreased from 52.3% to 30.6% (−909.43 km). The calculation showed that the transition from KB-65 to SKL, GK1 systems increases longitudinal resistance to rail creep by 25%, from 14.72 to 18.40 kN/m, while reducing the rail "breathing" zone length by 20%, from 83.5 to 66.8 m. The findings confirm the transition towards resilient baseplate-free fastening systems and substantiate the need for standardised diagnostics of the sleeper-fastening assembly. The obtained results may be applied in selecting fastening systems for major track repair sections and in substantiating measures to enhance the stability of CWR track on the JSC «NC KTZ» network.