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. 2021 Apr 21;13(9):1359.
doi: 10.3390/polym13091359.

Novel Bending Test Method for Polymer Railway Sleeper Materials

Choman Salih  1 , Allan Manalo  1 , Wahid Ferdous  1 , Rajab Abousnina  2 , Peng Yu  1 , Tom Heyer  3 , Peter Schubel  1
Affiliations

Novel Bending Test Method for Polymer Railway Sleeper Materials

Choman Salih et al. Polymers (Basel). .

Abstract

Alternative sleeper technologies have been developed to address the significant need for the replacement of deteriorating timber railway sleepers. The review of the literature indicates that the railway sleepers might fail while in service, despite passing the evaluation tests of the current composite sleeper standards which indicated that these tests do not represent in situ sleeper on ballast. In this research, a new five-point bending test is developed to evaluate the flexural behaviour of timber replacement sleeper technologies supported by ballast. Due to the simplicity, acceptance level of evaluation accuracy and the lack of in-service behaviour of alternative sleepers, this new testing method is justified with the bending behaviour according to the Beam on Elastic Foundation theory. Three timber replacement sleeper technologies-plastic, synthetic composites and low-profile prestressed concrete sleepers in addition to timber sleepers-were tested under service loading condition to evaluate the suitability of the new test method. To address the differences in the bending of the sleepers due to their different modulus of elasticities, the most appropriate material for the middle support was also determined. Analytical equations of the bending moments with and without middle support settlement were also developed. The results showed that the five-point static bending test could induce the positive and negative bending moments experienced by railway sleepers under a train wheel load. It was also found that with the proposed testing spans, steel-EPDM rubber is the most suitable configuration for low bending modulus sleepers such as plastic, steel-neoprene for medium modulus polymer sleepers and steel-steel for very high modulus sleepers such as concrete. Finally, the proposed bending moment equations can precisely predict the flexural behaviour of alternative sleepers under the five-point bending test.

Keywords: Beam on Elastic Foundation (BOEF); composite sleeper; five-point bending test; in-track sleeper behaviour; timber replacement sleeper.

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Conflict of interest statement

The authors declare no conflicts of interest. The funders had no role in the design of the study; in the collection, analyses or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.

Figures

Figure 1
Figure 1
Different shapes of alternative sleepers: (a) composite sleepers [28,29,30], (b) recycled plastic sleeper [31] and (c) alternative composite sleeper patent [32].
Figure 2
Figure 2
(a) Four-point bending test of a plastic sleeper without resilient pads [25]. (b) Spalling of the concrete surface under a steel plate [39].
Figure 3
Figure 3
(a) In−service bending shape of plastic and timber sleepers [43]. (b) Deflection profile of timber with and without reinforcement according to BOEF [44].
Figure 4
Figure 4
BOEF theory vs. five-point bending test.
Figure 5
Figure 5
Sleeper behaviour according to BOEF theory, five-point bending, rail seat and centre test.
Figure 6
Figure 6
Sleeper samples showing applied speckle pattern.
Figure 7
Figure 7
Actual test setup of the five-point bending test, showing the plastic sleeper.
Figure 8
Figure 8
Digital Image Correlation (DIC) images of the sleepers showing displacement points (neoprene support at centre).
Figure 9
Figure 9
Load–displacement graphs measured at rail seat and centre.
Figure 10
Figure 10
Full-length deflection shape of the sleepers for different support types.
Figure 11
Figure 11
Relationship of positive/negative moment ratio with sleeper stiffness.
Figure 12
Figure 12
Validation of the analytical solution with finite element (FE) analysis.
See this image and copyright information in PMC

References

    1. Zakeri J.-A., Rezvani F.H. Failures of railway concrete sleepers during service life. Int. J. Constr. Eng. Manag. 2012;1:1–5.
    1. Ferdous W., Manalo A., Van Erp G., Aravinthan T., Kaewunruen S., Remennikov A. Composite railway sleepers–Recent developments, challenges and future prospects. Compos. Struct. 2015;134:158–168. doi: 10.1016/j.compstruct.2015.08.058. - DOI
    1. Nosker T., Renfree R., Lynch J., Lutz M., Gillespie B., Lampo R., Van Ness K.E. Proceedings of the Technical Papers of The Annual Technical Conference-Society of Plastics Engineers Incorporated. Society of Plastics Engineers Inc.; Brookfield, CT, USA: 1998. A performance-based approach to the development of a recycled plastic/composite crosstie; pp. 2912–2915.
    1. Ju S., Yoon J., Sung D., Pyo S. Mechanical Properties of Coal Ash Particle-Reinforced Recycled Plastic-Based Composites for Sustainable Railway Sleepers. Polymers. 2020;12:2287. doi: 10.3390/polym12102287. - DOI - PMC - PubMed
    1. Nairn J., Stevens N. CORE 2010: Rail, Rejuvenation and Renaissance. Engineers Australia; Wellington, Australia: 2010. Rational design method for prestressed concrete sleepers; p. 174.

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