Experimental study on the longitudinal resistance of WJ-8 fasteners subjected to torque and vertical loading in continuously welded rails

Abstract

The key functions of the fastener system are to hold the rail against the sleepers and to restrain the rail from all forms of movements that could lead to loss of geometry and stability of the track. Thus, fastener resistance is an important parameter in the continuously welded rail technology. This study investigates the characteristics of the longitudinal resistance of WJ-8 fasteners subjected to varying torques and vertical loadings. The vertical loading was applied to the rail section through a reaction frame, while the torque was applied using a digital torque wrench. Two types of fasteners, conventional-resistance and small-resistance fasteners, were tested in this study. The study shows that: (1) The growth rate of the longitudinal resistance of the fastener is independent of the vertical loading until the fastener slips. (2) The slip resistance of fasteners increases as the torque and vertical loading are increased. (3) The relationship between the longitudinal resistance and the displacement of fasteners at varying torques and vertical loadings fits a power index function. (4) The relationship between the longitudinal resistance and the displacement of the fastener exhibits hysteresis. The study serves as a reference for verifying and improving future calculation methods for the longitudinal resistance of fasteners in continuously welded rails.

Keywords

Continuously welded rail WJ-8 fastener longitudinal resistance vertical loading torque hysteresis curve

Get full access to this article

View all access options for this article.

References

Ruge

Birk

. Longitudinal forces in continuously welded rails on bridge decks due to nonlinear track-bridge interaction. Comput Struct 2007; 85(7–8): 458–475.

Ruge

Widarda

Schmälzlin

, et al. Longitudinal track-bridge interaction due to sudden change of coupling interface. Comput Struct 2009; 87(1–2): 47–58.

Yan

Dai

Zhang

. Beam-track interaction of high-speed railway bridge with ballast track. J Central South Univ 2012; 19(5): 1447–1453.

Zhang

. Loading-history-based track-bridge interaction analysis with experimental fastener resistance. Eng Struct 2015; 83: 62–73.

Chen

Wang

Wei

. Track-bridge longitudinal interaction of continuous welded rails on arch bridge. Math Probl Eng 2013; 494137: 237–245.

Yan

Dai

Guo

, et al. Longitudinal force in continuously welded rail on long-span tied arch continuous bridge carrying multiple tracks. J Central South Univ 2015; 22(5): 2001–2006.

Luo

Zeng

. A novel algorithm for longitudinal track–bridge interactions considering loading history and using a verified mechanical model of fasteners. Eng Struct 2019; 183: 52–68.

Luo

. A model for predicting the effect of temperature force of continuous welded rail track. Proc IMechE, Part F: J Rail and Rapid Transit 1999; 213(2): 117–124.

Shao

Zhang

Xie

, et al. The longitudinal force measurement of CWR tracks with hetero-cladding FBG sensors: A proof of concept. Sensors 2016; 16(12): 2184.

10.

Gao

Zhai

. On effects of rail fastener failure on vehicle/track interactions. Struct Eng Mech 2017; 63(5): 659–667.

11.

Shi WQ and Cai CBA. Influence of slab track fastener failure on track dynamic performance. In: International symposium on environmental vibration, ISEV 2010: Advances in environmental vibration, Chengdu, China, 20–22 October 2011, pp.686–692, Beijing, Peoples R China: Science Press Beijing.

12.

Mohammadzadeh

Esmaeili

Khatibi

. A new field investigation on the lateral and longitudinal resistance of ballasted track. Proc IMechE, Part F: J Rail and Rapid Transit 2018; 232(8): 2138–2148.

13.

Lim

Han

, et al. Parametric study on stability of continuous welded rail track-ballast resistance and track irregularity. Int J Steel Struct 2008; 8(3): 171–181.

14.

Dai

Liu

. Applicability of small resistance fastener on long-span continuous bridges of high-speed railway. J Central South Univ 2013; 20(5): 1426–1433.

15.

Yang

Jang

. Track-bridge interaction analysis using interface elements adaptive to various loading cases. J Bridge Eng 2016; 21(9): 04016056.

16.

Qi SX, Liu H and Liu XY. Mechanical characteristics analysis of monolithic track bed with damper fastener on long ramp with large slope. In: ICRE 2014: construction and maintenance of railway infrastructure in complex environment, Beijing, China, 2–3 August 2014, pp.151–156, Beijing, Peoples R China: China Railway Publishing House.

17.

Yang

. Field trials and research on longitudinal resistance of WJ-7 and WJ-8 types resistance fasteners. Railway Stand Des 20102 51–52. [in Chinese].

18.

Guo

Yang

. Experiment of longitudinal resistance of WJ-8 type small resistance fastener with the sliding of rubber pad. J Railway Sci Eng 2015; 12(04): 749–754. [in Chinese].

19.

Wei

Yang

Dou

, et al. Experimental investigation into temperature- and frequency-dependent dynamic properties of high-speed rail pads. Constr Build Mater 2017; 151: 848–858.

20.

Wei

Wang

, et al. Effect of temperature- and frequency-dependent dynamic properties of rail pads on high-speed vehicle-track coupled vibrations. Vehicle Syst Dyn 2017; 55(3): 351–370.

21.

Chinese National Standards, TB/T 10082-2017, Code for Design of Railway Track, Beijing, 2017 [in Chinese].

22.

British Standard. EN 13481 Railway applications–track–performance requirements for fastening systems, 2006.

23.

British Standard. EN 13146 Railway applications–track–test methods for fastening systems, 2012.

24.

Chinese national standards, TB/T 3395.5-2015, Fastening systems for high-speed railway Part 5: WJ-8 fastening system, Beijing, 2015 [in Chinese].

25.

Gao L. Research and application of key technology of CWR track on high speed railway. Beijing: China Railway Press, 2012 [in Chinese].