Next Article in Journal
Machine Learning and Optimality in Multi Storey Reinforced Concrete Frames
Previous Article in Journal
Comment on: Toughness of Railroad Concrete Crossties with Holes and Web Openings. Infrastructures 2017, 2, 3
 
 
Order Article Reprints
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Reply

Reply to Giannakos, K. Comment on: Toughness of Railroad Concrete Crossties with Holes and Web Openings. Infrastructures 2017, 2, 3

1
Department of Civil Engineering, School of Engineering, The University of Birmingham, Edgbaston B15 2TT, UK
2
Birmingham Centre for Railway Research and Education, School of Engineering, The University of Birmingham, Edgbaston B15 2TT, UK
3
School of Civil, Mining, and Environmental Engineering, University of Wollongong, Northfield Ave, Wollongong, NSW 2522, Australia
4
Concrete Laboratory, Department of Civil Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
*
Author to whom correspondence should be addressed.
Infrastructures 2017, 2(2), 5; https://doi.org/10.3390/infrastructures2020005
Received: 8 March 2017 / Revised: 8 March 2017 / Accepted: 8 April 2017 / Published: 13 April 2017
This paper responds to the discussion [1] by Dr. K. Giannakos over our technical note [2]. In fact, the authors welcome any comments to improve our research and practical experience related to railway sleepers. In the discussion comment letter [1], Dr Giannakos discussed whether or not static testing of railway prestressed concrete sleepers has any value in the engineering field. The discusser based his comments on the need for dynamic testing for the determination of the bearing capacity of concrete sleepers on the provisions from EN13230-2 and also inappropriately stated that ‘it is misleading to use static not dynamic tests’.
Based on our extensive experience in both actual rail industry and academia (exemplified evidences in Refs: [2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121]), it is very well known that railway concrete sleepers (or railroad ties) are a structural and safety-critical component in track systems. Their main duties are to distribute the load as well as to secure rail gauge during train passages. Although there exist two design principles (permissible stress and limit states design concepts), their design takes into account both static and dynamic loading conditions together with their associated static and dynamic structural behaviours [122,123,124]. Despite the use of the prestressed concrete sleepers in railway networks over 55 years, their design and behaviour are neither thoroughly understood nor well documented. In particular, little information is available when the concrete sleepers are modified ad hoc and in situ. Without appropriate structural design and engineering analysis, the structural safety and engineering reliability of railway track systems can be impaired or mismanaged. A critical review of existing standard design codes (e.g., European Standard EN13230-2, American Standard AREMA C4, Australian Standard AS1095.14, or American Concrete Institute, ACI) reveals that there is a necessity to investigate such the important aspects [1]. On this ground, it is important to note that it is the first time that the effect of holes and web openings on the toughness and ductility of concrete sleepers is addressed in a systematic way [2]. Static testing is the first step in studying the behaviour of sleepers with holes and web openings, which was presented in [2] to inform the engineering community about the initial results, and dynamic testing is the next step forward (to be published in due course). The improved understanding will help railway and track engineers to determine structurally appropriate retrofitting approaches for prestressed concrete sleepers with the holes and web openings in practice.
Based on the international railway practices, there are two main design principles that have been commonly used to describe or predict the behaviour of railway sleepers (using any type of materials) [4,5]. The traditional design method that has been used for over many decades is based on the ‘permissible stress design principle’ while the new performance-based design method considers ‘limit states design concept’ [28,29]. The life span of concrete sleepers can also be varied. In Australasia, North America, Asia and South Africa, the sleeper design life is about 50 years since the uncertainties have been considered in design and maintenance (asset operations). In Europe, the sleepers must last more than 70 years. In addition, each country has adopted different material testing methods that resulted in different materials’ strength and behaviour used in the design processes. With these factors in mind, a key performance criterion in the existing design principles (i.e., limit states design concept and permissible stress design principle) still rely on the ultimate capacity from the combined static stresses. In a structural design, ample ultimate strength and capacity of engineering structures and components must always be ascertained [124,125,126,127]. It is important to note that the ultimate capacity of the structural concrete members indicates many structural features with respect to dynamic and service performance of the components [128,129,130,131].
In reality, railway track structures are often subjected to the dynamic loading conditions due to wheel/rail interactions associated with the abnormalities in either a wheel or a rail [3]. The magnitude of the dynamic impact loads per railseat can vary from 200 kN and can sometimes be more than 600 kN, whilst the design static wheel load per railseat for a 40-tone axle load could be only as much as 110 kN [120,121]. All static, quasi-static, and impact loads are very important in the design and analysis of a railway track and its components. Generally, dynamic loading corresponds to the frequency range from 0 to 2000 Hz due to modern design of track vehicles. The shape of impact loading varies depending on various possible sources of such loading, e.g., wheel flats, out-of-round wheels, wheel corrugation, short and long wavelength rail corrugation, dipped welds and joints, pitting, and shelling. Wheel/rail irregularities induce high dynamic impact forces along the rails that may greatly exceed the static wheel load. In general, the dynamic load characteristics are considered in the design and analysis using ‘impact factor’ or ‘dynamic amplification factor’. All of the design methods embrace the factor in the calculation of principal static stresses and their redistribution. This is the reason why ultimate static response has come to play a key role and why static behaviour is essential to enable structural failure mode prediction.
Figure 1 shows an actual statistical data of annual wheel loading obtained from railway networks in Australia. This track force measurement offers a clear insight that the dynamic load cases used in standard type tests (i.e., prescribed in EN13230-2) are not supposed to apply for understanding the sleeper behaviour. In fact, the prescribed dynamic load cases are adopted for performance benchmarking purpose. On this basis, the research presented in [2] is not misleading but, on the other hand, offers unparalleled insight into sleeper behaviours under the specific conditions (with holes and web openings). The insight into sleepers’ toughness and ductility will ensure that any concrete sleeper can be structurally, safely retrofitted and modified for add-on fixture in practice.
The permissible stress design concept has fundamentally dominated in current Australian and most international design standards for prestressed concrete sleepers where various limiting values or reduction factors are imposed on material strengths and load effects. Alternatively, the limit states design concept is a more logical entity for use as the design approach for prestressed concrete sleepers, in a similar manner to structural concrete members. It considers both strength and serviceability. A simple pseudo-static (using factored load) approach can be used in the design procedures of concrete sleepers under routine traffics. The new limit states design concept has been developed from comprehensive studies of the loading conditions, the static behaviour, the dynamic response, and the impact resistance of the prestressed concrete sleepers.
Figure 2 shows the flowchart for reliability-based structural design of railway concrete sleepers [89]. The errors and uncertainties involved in the estimation of the limit states design loads on the behaviour of a structure may be allowed for in strength design by using load factors to increase the nominal loads and using capacity factors to decrease the structural strength. The purpose of using any factor is to ensure that the probability of failure under the most adverse conditions of structural overload remains very small, which may be implicit or explicit in the rules written in a code. In structural design practices, toughness of a member is an important factor in the fail-safe design of structural systems, especially for the failure mode identification at ultimate state. The toughness characteristic has correlation with dynamic strength and endurance of structural members. In the technical note [1], the emphasis was placed on experimental investigations into structural toughness, which is an important characteristic to predict failure under ultimate and damageability limit states [39,85,135]. As such, there is no shortage of value since the research in [2] paves the essential fundamental for further research into sleepers’ retrofit and modification. In addition, numerical study can use static test data for validation and enable virtual tests of the sleepers with holes and web openings under different limit states (i.e., dynamic and impact conditions due to accidental loading, fatigue life or endurance characteristics, etc.).
For dynamically compliant structures such as railway tracks, the fatigue life or endurance characteristic would likely be another factor in the serviceability limit state [39,85] because low and high cycle fatigue failure of railway sleepers may occur. Fatigue performance or ‘endurance’ of sleepers can be correlated to energy toughness [125,129]. In most cases, a ratio of dynamic over static performance is often used in asset modelling and management. Static tests are normally served as a datum or reference. Without static testing, the dynamic accumulative results are meaningless [20,21,136]. Additionally, it is noted from [136] that “According to the standard (EN13230), the dynamic testing is regarded as non-obligatory optional testing that is conducted at the request of the end-user. The results obtained confirmed the reasons why standards do not require dynamic testing: dynamic (impact) safety coefficients obtained in the testing, compared to maximum allowable values, are greater than the relationship between the static safety coefficients and maximum allowable static safety coefficients. It is clear that the effect involving increase of bearing capacity of prestressed concrete sleepers occurs at dynamic cyclic load.” [136]. This finding is similar to a trend found in the past [129]. However, based on our previous relevant research [2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121], this fatigue serviceability limit state is critical for aging sleepers and should be considered for load rating [34,35].
In summary, the standard type testing has been developed and adopted for performance benchmarking. The technical note (under the discussion) neither misleads nor provides negligible value. In contrast, the work provides a fundamental step towards better correlation between endurance and toughness of sleepers with holes and web openings. It also improves the insight into structural failure that helps railway track engineers determine appropriate ad hoc and in situ modification methods for the structural and safety-critical components in railway track systems. The goal is to improve public safety and reduce unplanned track maintenance (contributing towards extra costs, time, energy and carbon footprint) due to premature failure of railway sleepers [137,138]. On this ground, by inappropriately publishing his comment, the discusser harassed the authors by unfairly accusing them of providing misleading research information.

Conflicts of Interest

No conflict of interest.

References

  1. Giannakos, K. Comment on: Toughness of Railroad Concrete Crossties with Holes and Web Openings. Infrastructures 2017, 2, 3. Infrastructures 2017, 2, 4. [Google Scholar] [CrossRef]
  2. Gamage, E.K.; Kaewunruen, S.; Remennikov, A.M.; Ishida, T. Toughness of Railroad Concrete Crossties with Holes and Web Openings. Infrastructures 2017, 2, 3. [Google Scholar] [CrossRef]
  3. Remennikov, A.M.; Kaewunruen, S. A review on loading conditions for railway track structures due to wheel and rail vertical interactions. Struct. Control Health Monit. 2008, 15, 207–234. [Google Scholar] [CrossRef]
  4. Remennikov, A.M.; Murray, M.H.; Kaewunruen, S. Conversion of AS1085.14 for railway prestressed concrete sleeper to limit states design format. In Proceedings of the AusRAIL Plus 2007, Sydney, Australia, 2–6 December 2007. [CD-Rom]. [Google Scholar]
  5. Remennikov, A.M.; Murray, M.H.; Kaewunruen, S. Reliability based conversion of a structural design code for prestressed concrete sleepers. Proc. Inst. Mech. Eng. J. Rail Rapid Transit 2012, 226, 155–173. [Google Scholar] [CrossRef]
  6. Remennikov, A.; Kaewunruen, S. Experimental investigation on dynamic railway sleeper/ballast interaction. Exp. Mech. 2006, 46, 57–66. [Google Scholar] [CrossRef]
  7. Kaewunruen, S.; Remennikov, A.M. Sensitivity analysis of free vibration characteristics of an in-situ railway concrete sleeper to variations of rail pad parameters. J. Sound Vib. 2006, 298, 453–461. [Google Scholar] [CrossRef]
  8. Kaewunruen, S.; Remennikov, A.M. Experimental and numerical studies of railway prestressed concrete sleepers under static and impact loads. J. Civ. Comput. 2007, 25–28. [Google Scholar]
  9. Kaewunruen, S.; Remennikov, A.M. Effect of improper ballast tamping/packing on dynamic behaviors of on-track railway concrete sleeper. Int. J. Struct. Stab. Dyn. 2007, 7, 167–177. [Google Scholar] [CrossRef]
  10. Kaewunruen, S.; Remennikov, A.M. Field trials for dynamic characteristics of railway track and its components using impact excitation technique. NDT E Int. 2007, 40, 510–519. [Google Scholar] [CrossRef]
  11. Kaewunruen, S.; Remennikov, A.M. Investigation of free vibrations of voided concrete sleepers in railway track system. Proc. IMechE F J. Rail Rapid Transit 2007, 221, 495–508. [Google Scholar] [CrossRef]
  12. Kaewunruen, S.; Remennikov, A.M. An alternative rail pad tester for measuring dynamic properties of rail pads under large preloads. Exp. Mech. 2008, 48, 55–64. [Google Scholar] [CrossRef]
  13. Kaewunruen, S.; Remennikov, A.M. Experimental determination of the effect of wet/dry ballast on dynamic sleeper/ballast interaction. ASTM J. Test. Eval. 2008, 36, 412–415. [Google Scholar]
  14. Kaewunruen, S.; Remennikov, A.M. Probabilistic impact fractures of railway prestressed concrete sleepers. Adv. Mater. Res. 2008, 41–42, 259–264. [Google Scholar] [CrossRef]
  15. Kaewunruen, S.; Remennikov, A.M. Dynamic effect of vibration signatures of cracks in railway prestressed concrete sleepers. Adv. Mater. Res. 2008, 41–42, 233–239. [Google Scholar] [CrossRef]
  16. Kaewunruen, S.; Remennikov, A.M. Experimental simulation of the railway ballast by resilient materials and its verification by modal testing. Exp. Tech. 2008, 4, 29–35. [Google Scholar] [CrossRef]
  17. Kaewunruen, S.; Remennikov, A.M. Effect of a large wheel impact burden on flexural response and failure of railway concrete sleepers in track systems. Eng. Fail. Anal. 2008, 15, 1065–1075. [Google Scholar] [CrossRef]
  18. Kaewunruen, S.; Remennikov, A.M. Nonlinear transient analysis of railway concrete sleepers in track systems. Int. J. Struct. Stab. Dyn. 2008, 8, 505–520. [Google Scholar] [CrossRef]
  19. Kaewunruen, S.; Remennikov, A.M. Dynamic flexural influence on railway concrete sleepers in track systems of a wheel impact. Eng. Fail. Anal. 2009, 16, 705–712. [Google Scholar] [CrossRef]
  20. Kaewunruen, S.; Remennikov, A.M. Impact fatigue responses of railway prestressed concrete sleepers. IES J. Civ. Struct. Eng. 2009, 2, 47–58. [Google Scholar]
  21. Kaewunruen, S.; Remennikov, A.M. Impact capacity of railway prestressed concrete sleepers. Eng. Fail. Anal. 2009, 16, 1520–1532. [Google Scholar] [CrossRef]
  22. Kaewunruen, S.; Remennikov, A.M. Structural safety of railway prestressed concrete sleepers. Aust. J. Struct. Eng. 2009, 9, 129–140. [Google Scholar]
  23. Kaewunruen, S.; Remennikov, A.M. State-dependent properties of rail pads. Transp. Eng. 2009, 11, 17–24. [Google Scholar]
  24. Kaewunruen, S.; Remennikov, A.M. Influence of ballast conditions on flexural responses of railway concrete sleepers in track systems. J. Concr. Inst. Aust. 2009, 35, 57–62. [Google Scholar]
  25. Kaewunruen, S.; Remennikov, A.M. Progressive failure of prestressed concrete sleepers under multiple high-intensity impact loads. Eng. Struct. 2009, 31, 2460–2473. [Google Scholar] [CrossRef]
  26. Kaewunruen, S.; Remennikov, A.M. Dynamic crack propagations of prestressed concrete sleepers in railway track systems subjected to severe impact loads. ASCE J. Struct. Eng. 2010, 136, 749–754. [Google Scholar] [CrossRef]
  27. Kaewunruen, S.; Remennikov, A.M. Dynamic properties of railway track and its components: Recent finding and future research directions. Insight-Non-Destr. Test. Cond. Monit. 2010, 52, 20–22. [Google Scholar]
  28. Kaewunruen, S.; Remennikov, A.M.; Murray, M.H. Greener & Leaner: Unleashing the capacity of railroad concrete ties. ASCE J. Struct. Eng. 2011, 137, 241–247. [Google Scholar]
  29. Kaewunruen, S.; Remennikov, A.M.; Murray, M.H. Limit states design of concrete sleepers. ICE Transp. 2011, 165, 81–85. [Google Scholar]
  30. Kaewunruen, S.; Remennikov, A.M. Ultimate impact resistance and residual toughness of prestressed concrete railway sleepers. Aust. J. Struct. Eng. 2011, 12, 87–97. [Google Scholar]
  31. Kaewunruen, S.; Remennikov, A.M. Experiments into impact behaviours of railway prestressed concrete sleepers. Eng. Fail. Anal. 2011, 18, 2305–2315. [Google Scholar] [CrossRef]
  32. Kaewunruen, S.; Remennikov, A.M. On the residual energy toughness of prestressed concrete sleepers in railway track structures subjected to repeated impact loads. Electron. J. Struct. Eng. 2013, 13, 41–61. [Google Scholar]
  33. Kaewunruen, S. Monitoring in-service performance of fibre-reinforced foamed urethane material as timber-replacement sleepers/bearers in railway urban turnout systems. Struct. Monit. Maint. 2014, 1, 131–157. [Google Scholar]
  34. Remennikov, A.M.; Kaewunruen, S. Determination of remaining prestressing force in concrete sleepers using dynamic relaxation technique. ASCE J. Perform. Constr. Facil. 2014, 29, 04014134. [Google Scholar] [CrossRef]
  35. Remennikov, A.M.; Kaewunruen, S. Experimental load rating of aged prestressed concrete sleepers. Eng. Struct. 2014, 76, 147–162. [Google Scholar] [CrossRef]
  36. Kaewunruen, S.; Remennikov, A.M.; Aikawa, A.; Sato, H. Free vibrations of interspersed railway track systems in three-dimensional space. Acoust. Aust. 2014, 14, 20–26. [Google Scholar]
  37. Kaewunruen, S. Monitoring structural deterioration of railway turnout systems via dynamic wheel/rail interaction. Case Stud. Nondestruct. Test. Eval. 2014, 1, 19–24. [Google Scholar] [CrossRef]
  38. Kaewunruen, S. Impact damage mechanism and mitigation by ballast bonding at railway bridge ends. Int. J. Railw. Tech. 2014, 3, 1–22. [Google Scholar] [CrossRef]
  39. Kaewunruen, S.; Remennikov, A.M.; Murray, M.H. Introducing limit states design concept to concrete sleepers: An Australian experience. Front. Mater. 2014, 1, 1–3. [Google Scholar] [CrossRef]
  40. Griffin, D.W.P.; Mirza, O.; Kwok, K.; Kaewunruen, S. Composites for railway construction and maintenance: A mechanistic review. IES J. Civ. Struct. Eng. 2014, 7, 243–262. [Google Scholar]
  41. Kaewunruen, S.; Ishida, M. Field monitoring of rail squats using 3D ultrasonic mapping technique. J. Can. Inst. Non-Destruct. Eval. 2014, 35, 5–11. [Google Scholar]
  42. Kaewunruen, S.; Ishida, M. In situ monitoring of rail squats in three dimensions using ultrasonic technique. Exp. Tech. 2016, 40, 1179–1185. [Google Scholar] [CrossRef]
  43. Kaewunruen, S.; Ishida, M.; Marich, S. Dynamic wheel-rail interaction over rail squat defects. Acoust. Aust. 2015, 43, 97–107. [Google Scholar] [CrossRef]
  44. Griffin, D.W.P.; Mirza, O.; Kwok, K.; Kaewunruen, S. Finite element modelling of modular precast composites for railway track support structure—A battle to save Sydney Harbour Bridge. Aust. J. Struct. Eng. 2015, 16, 150–168. [Google Scholar] [CrossRef]
  45. Kaewunruen, S.; Sussman, J.M.; Einstein, H.H. Strategic framework to achieve carbon-efficient construction and maintenance of railway infrastructure systems. Front. Environ. Sci. 2015, 3, 6. [Google Scholar] [CrossRef]
  46. Sae Siew, J.; Mirza, O.; Kaewunruen, S. Nonlinear finite element modelling of railway turnout system considering bearer/sleeper-ballast interaction. J. Struct. 2015, 2015, 598562. [Google Scholar] [CrossRef]
  47. Krezo, S.; Mirza, O.; He, Y.; Makim, P.; Kaewunruen, S. Field investigation and parametric study of greenhouse gas emissions from railway plain-line renewals. Transp. Res. Transp. Environ. 2015, 42, 77–90. [Google Scholar] [CrossRef]
  48. Mirza, O.; Kaewunruen, S.; Galia, G. Seismic vulnerability analysis of Bankstown’s West Terrace railway bridge. Struct. Eng. Mech. 2015, 57, 569–585. [Google Scholar] [CrossRef]
  49. Ferdous, W.; Manalo, A.; Van Erp, G.; Aravinthan, T.; Kaewunruen, S.; Remennikov, A.M. Composite Railway Sleepers—Recent developments, challenges and future prospects. Compos. Struct. 2015, 134, 158–168. [Google Scholar] [CrossRef]
  50. Kaewunruen, S.; Remennikov, A.M. An overview of current state of practice in track vibration isolation. Aust. J. Civ. Eng. 2016, 14, 63–71. [Google Scholar] [CrossRef]
  51. Mirza, O.; Kaewunruen, S.; Donh, C.; Pervanic, E. Numerical investigation into thermal load responses of railway transom bridge. Eng. Fail. Anal. 2016, 60, 280–295. [Google Scholar] [CrossRef]
  52. Kaewunruen, S. Systems thinking approach for rail freight noise mitigation. Acoust. Aust. 2016, 44, 193–194. [Google Scholar] [CrossRef]
  53. Kaewunruen, S.; Meesit, R. Sensitivity of crumb rubber particle sizes on electrical resistance of rubberised concrete. Cogent Eng. 2016, 3, 1126937. [Google Scholar] [CrossRef]
  54. Tavares de Freitas, R.; Kaewunruen, S. Life Cycle Cost Evaluation of Noise and Vibration Control Methods at Urban Railway Turnouts. Environments 2016, 3, 34. [Google Scholar] [CrossRef]
  55. Tuler, M.V.; Kaewunruen, S. Life cycle analysis of mitigation methodologies for railway rolling noise and groundbourne vibration. J. Environ. Manag. 2017, 191, 75–82. [Google Scholar] [CrossRef] [PubMed]
  56. Binti Sa’adin, S.L.; Kaewunruen, S.; Jaroszweski, D. Risks of Climate Change on the Singapore-Malaysia High Speed Rail System. Climate 2016, 4, 65. [Google Scholar] [CrossRef]
  57. Binti Sa’adin, S.L.; Kaewunruen, S.; Jaroszweski, D. Operational readiness for climate change of Malaysia high-speed rail. Proc. Inst. Civ. Eng. Transp. 2016, 169, 308–320. [Google Scholar] [CrossRef]
  58. Dindar, S.; Kaewunruen, S.; An, M. Identification of Appropriate Risk Analysis Techniques for Railway Turnout Systems. J. Risk Res. 2016. [Google Scholar] [CrossRef]
  59. Sae Siew, J.; Mirza, O.; Kaewunruen, S. Torsional effect on railway track structures of turnout crossing impact. ASCE J. Transp. Eng. Syst. 2016, in press. [Google Scholar] [CrossRef]
  60. Kaewunruen, S.; Meesit, R.; Mondal, P. Early-age dynamic moduli of crumbed rubber concrete for compliant railway structures. J. Sustain. Cem. Based Mater. 2017. [Google Scholar] [CrossRef]
  61. Meesit, R.; Kaewunruen, S. Vibration characteristics of micro-engineered crumb rubber concrete for railway sleeper applications. J. Adv. Concr. Technol. 2017, 15, 55–66. [Google Scholar] [CrossRef]
  62. Kaewunruen, S. Monitoring of rail corrugation growth on sharp curves for track maintenance prioritization. Int. J. Acoust. Vib. 2017, in press. [Google Scholar]
  63. Gamage, E.; Kaewunruen, S.; Remennikov, A.M. Design of holes and web openings in railway prestressed concrete sleepers. In Proceedings of the 13th International Railway Engineering Conference, Edinburgh, UK, 28 June–2 July 2015. [Google Scholar]
  64. Vu, M.; Kaewunruen, S.; Attard, M. Nonlinear 3D finite element modeling for structural failure analysis of concrete bearers at a railway urban turnout diamond. In Handbook of Materials Failure Analysis; Elsevier: Amsterdam, The Netherlands, 2015; pp. 123–160. [Google Scholar]
  65. Kaewunruen, S.; Gamage, E.K.; Remennikov, A.M. Structural behaviours of railway prestressed concrete sleepers (crossties) with hole and web openings. Procedia Eng. 2016, 161, 1247–1253. [Google Scholar] [CrossRef]
  66. Kaewunruen, S.; Gamage, E.K.; Remennikov, A.M. Modelling railway prestressed concrete sleepers (crossties) with hole and web openings. Procedia Eng. 2016, 161, 1240–1246. [Google Scholar] [CrossRef]
  67. Mirza, O.; Kaewunruen, S.; Kwok, K.; Griffin, D.W.P. Design and modelling of pre-cast steel-concrete composites for resilient railway track slabs. Steel Compos. Struct. Int. J. 2016, 22, 537–565. [Google Scholar] [CrossRef]
  68. Kaewunruen, S.; Chamniprasart, K. Damage analysis of spot replacement sleepers interspersed in ballasted railway tracks. In Proceedings of the 29th Nordic Seminar on Computational Mechanics, Chalmers University of Technology, Gothenburg, Sweden, 28–30 October 2016. [Google Scholar]
  69. Kaewunruen, S.; Minoura, S.; Watanabe, T.; Remennikov, A.M. Remaining service life of railway prestressed concrete sleepers. In Proceedings of the International RILEM Conference on Materials, Systems and Structures in Civil Engineering, Technical University of Denmark, Lyngby, Denmark, 22–24 August 2016. [Google Scholar]
  70. Setsobhonkul, S.; Kaewunruen, S. Life cycle analysis of railway noise and vibration mitigation methodologies with respect to curve squeal noises. In Proceedings of the 45th International Congress and Exposition on Noise Control Engineering INTER-NOISE 2016, Humburg, Germany, 22 August 2016; pp. 1–10. [Google Scholar]
  71. Kaewunruen, S.; Remennikov, A.M.; Nguyen, P.; Aikawa, A. Field performance to mitigate impact vibration at railway bridge ends using soft baseplates. In Proceedings of the 11th World Congress on Railway Research, Milan, Italy, 30 May–1 June 2016. [Google Scholar]
  72. Kaewunruen, S.; Remennikov, A.M.; Aikawa, A. Effectiveness of Soft Baseplates and Fastenings to Mitigate Track Dynamic Settlement at Transition Zones on Railway Bridge Approaches. In Proceedings of the Third International Conference on Railway Technology: Research, Development and Maintenance; Pombo, J., Ed.; Civil-Comp Press: Stirlingshire, UK, 2016; Paper 197. [Google Scholar] [CrossRef]
  73. Kaewunruen, S.; Ishida, M. In Situ Monitoring of Multi-Stage Rail Surface Defects in Three Dimensions using a Mobile Ultrasonic Technique. In Proceedings of the Third International Conference on Railway Technology: Research, Development and Maintenance; Pombo, J., Ed.; Civil-Comp Press: Stirlingshire, UK, 2016; Paper 249. [Google Scholar] [CrossRef]
  74. Kaewunruen, S. Identification and prioritization of rail squat defects in the field using rail magnetisation technology. Proc. SPIE 2015. [Google Scholar] [CrossRef]
  75. Gamage, E.K.; Kaewunruen, S.; Remennikov, A.M. Design of holes and web openings in railway prestressed concrete sleepers. In Proceedings of the 13th International Railway Engineering Conference, Edinburgh, UK, 30 June–1 July 2015. [CD-Rom]. [Google Scholar]
  76. Kaewunruen, S.; Ishida, T.; Remennikov, A.M. Numerical simulations of negative flexural responses (hogging) in railway prestressed concrete sleepers. In Proceedings of the RILEM International Conference on Strategies for Sustainable Concrete, Rio de Janeiro, Brazil, 14–16 December 2015. [Google Scholar]
  77. Kaewunruen, S.; Jara Faria, K. Diagnostic of flexural damage on railway prestressed concrete sleeper using dynamic modal parameters. In Proceedings of the RILEM International Conference on Strategies for Sustainable Concrete, Rio de Janeiro, Brazil, 14–16 December 2015. [Google Scholar]
  78. Kaewunruen, S.; Remennikov, A.M. Under sleeper pads: Field investigation of their role in detrimental impact mitigation. In Proceedings of the 13th International Railway Engineering Conference, Edinburgh, UK, 30 June–1 July 2015. [CD-Rom]. [Google Scholar]
  79. Kaewunruen, S.; Remennikov, A.M. Impact responses of pre-stressing tendons in railway concrete sleepers in high speed rail environments. In Proceedings of the 5th ECCOMAS Thematic Conference on Computational Methods in Structural Dynamics and Earthquake Engineering, Crete Island, Greece, 25–27 May 2015. [Google Scholar]
  80. Kaewunruen, S. Acoustic and dynamic characteristics of a complex urban turnout using fibre-reinforced foamed urethane (FFU) bearers. In Noise and Vibration Mitigation for Rail Transportation Systems; Nielsen, J.C.O., Ed.; Notes on Numerical Fluid Mechanics and Multidisciplinary Design; Springer: Berlin, Germany, 2015; pp. 377–384. [Google Scholar]
  81. Kaewunruen, S. Effectiveness of using elastomeric pads to mitigate impact vibrations at an urban turnout crossing. In Noise and Vibration Mitigation for Rail Transportation Systems; Maeda, T., Ed.; Notes on Numerical Fluid Mechanics and Multidisciplinary Design; Springer: Berlin, Germany, 2012; pp. 357–365. [Google Scholar]
  82. Kaewunruen, S.; Remennikov, A.M. Trends in vibration-based structural health monitoring of railway sleepers. In Mechanical Vibration: Measurement, Effect, and Control; Sapri, R.C., Ed.; Nova Science Publishers: New York, NY, USA, 2008. [Google Scholar]
  83. Kaewunruen, S.; Remennikov, A.M. Application of vibration measurements and finite element model updating for structural health monitoring of ballasted railtrack sleepers with voids and pockets. In Mechanical Vibration: Measurement, Effect, and Control; Sapri, R.C., Ed.; Nova Science Publishers: New York, NY, USA, 2008. [Google Scholar]
  84. Kaewunruen, S.; Remennikov, A.M. Dynamic properties of railway track and its components: A state-of-the-art review. In New Research on Acoustics; Weiss, B.N., Ed.; Nova Science Publishers: New York, NY, USA, 2008; pp. 197–220. [Google Scholar]
  85. Remennikov, A.M.; Kaewunruen, S. Reliability based design of railway prestressed concrete sleepers. In Book Chapter 3, Reliability Engineering Advances; Hayworth, G.I., Ed.; Nova Science Publishers: New York, NY, USA, 2009. [Google Scholar]
  86. Kaewunruen, S. Railway bridge end improvement using ballast glue. In Proceedings of the Railway 2014: The Second International Conference on Railway Technology: Research, Development, and Maintenance, Ajaccio, France, 8–11 April 2014. [Google Scholar]
  87. Kaewunruen, S.; Churchill, A.; Couper, J.; Kerr, M. Insitu performance of a complex urban turnout using fibre-reinforced foamed urethane (FFU) bearers. In Proceedings of the World Congress on Railway Research, Sydney, Australia, 24–27 November 2013. [Google Scholar]
  88. Wilson, A.; Kerr, M.B.; Marich, S.; Kaewunruen, S. Wheel/rail conditions and squat development on moderately curved tracks. In Proceedings of the Conference of Railway Engineering, Brisbane, Australia, 17–19 November 2012. [Google Scholar]
  89. Kaewunruen, S.; Remennikov, A.M.; Murray, M.H. Development of reliability-based design for railway prestressed concrete sleepers. In Proceedings of the 17th National Convention on Civil Engineering, Udonthani, Thailand, 9–11 May 2012. [Google Scholar]
  90. Kaewunruen, S.; Remennikov, A.M.; Aikawa, A. A numerical study to evaluate dynamic responses of voided concrete railway sleepers to impact loading. In Proceedings of the Acoustics Australia Conference 2011, Gold Coast, Australia, 2–4 November 2011. [CD-Rom]. [Google Scholar]
  91. Sun, Y.Q.; Cole, C.; Kerr, M.B.; Kaewunruen, S. Use of simulations in determination of wheel impact forces P1 and P2 due to rail dip defects. In Proceedings of the AusRAIL Plus 2009, Sydney, Australia, 17–19 November 2009; pp. 1–11. [Google Scholar]
  92. Kaewunruen, S.; Remennikov, A. Relation between impact energy and fracture toughness of prestressed concrete railway sleepers. In Proceedings of the Concrete 2009: Concrete Institute of Australia’s 24th Biennial Conference, Sydney, Australia, 19–21 September 2009. [CD-Rom]. [Google Scholar]
  93. Sun, Y.Q.; Cole, C.; McClanachan, M.; Wilson, A.; Kaewunruen, S.; Kerr, M.B. Rail short-wavelength irregularity identification based on wheel-rail impact response measurements and simulations. In Proceedings of the 9th International Heavy Haul Conference, Shanghai, China, 22–25 June 2009; pp. 210–218. [Google Scholar]
  94. Remennikov, A.M.; Murray, M.H.; Kaewunruen, S. Dynamic design guidelines for railway prestressed concrete sleepers. In Proceedings of the 20th Australasian Conference on the Mechanics of Structures and Materials, Toowoomba, Queensland, Australia, 19–21 December 2008. [CD-Rom]. [Google Scholar]
  95. Kaewunruen, S.; Remennikov, A. Impact damage classification of railway prestressed concrete sleepers. In Proceedings of the Conference on Railway Engineering—CORE-2008, Perth, Australia, 7–10 September 2008; pp. 95–102. [Google Scholar]
  96. Kaewunruen, S.; Remennikov, A. An experimental evaluation of the attenuation effect of rail pad on flexural behaviour of railway concrete sleeper under impact loads. In Proceedings of the Australasian Structural Engineering Conference—ASEC2008, Melbourne, Australia, 26–27 June 2008. [CD-Rom]. [Google Scholar]
  97. Kaewunruen, S.; Remennikov, A. Reliability assessment of railway prestressed concrete sleepers. In Proceedings of the Australasian Structural Engineering Conference—ASEC2008, Melbourne, Australia, 26–27 June 2008. [CD-Rom]. [Google Scholar]
  98. Kaewunruen, S.; Remennikov, A. Low-velocity impact analysis of prestressed concrete sleepers. In Proceedings of the Concrete Institute of Australia’s 23rd Biennial Conference 07, Adelaide, Australia, 18–20 October 2007. [CD-Rom]. [Google Scholar]
  99. Remennikov, A.; Kaewunruen, S. Resistance of railway concrete sleepers to impact loading. In Proceedings of the 7th International Conference on Shock and Impact Loads on Structures, Beijing, China, 17–19 October 2007. [CD-Rom]. [Google Scholar]
  100. Remennikov, A.; Kaewunruen, S. Experimental determination of energy absorption capacity for railway prestressed concrete sleepers under impact loading. In Proceedings of the International Conference on Structural Engineering and Construction—ISEC2007, Melbourne, Australia, 26–28 September 2007. [CD-Rom]. [Google Scholar]
  101. Remennikov, A.; Kaewunruen, S. Simulating shock loads in railway track environments: Experimental studies. In Proceedings of the 14th International Congress on Sound and Vibration, Cairns, Australia, 9–12 July 2007. [CD-Rom]. [Google Scholar]
  102. Kaewunruen, S.; Remennikov, A. Relationship between wheel/rail interface impact and railseat flexural moment of railway PC sleeper. In Proceedings of the Society of Experimental Mechanics (SEM) Annual Conference and Exhibition 2007, Springfield, MA, USA, 3–6 June 2007. [CD-Rom]. [Google Scholar]
  103. Kaewunruen, S.; Remennikov, A. Influence of voids and pockets on the vibration characteristics of prestressed concrete sleepers. In Proceedings of the Society of Experimental Mechanics (SEM) Annual Conference and Exhibition 2007, Springfield, MA, USA, 3–6 June 2007. [CD-Rom]. [Google Scholar]
  104. Kaewunruen, S.; Remennikov, A. Investigations on static and dynamic performance of railway prestressed concrete sleepers. In Proceedings of the Society of Experimental Mechanics (SEM) Annual Conference and Exhibition 2007, Springfield, MA, USA, 3–6 June 2007. [CD-Rom]. [Google Scholar]
  105. Remennikov, A.; Kaewunruen, S. Impact resistance of reinforced concrete columns: Experimental studies and design considerations. In Proceedings of the 19th Australasian Conference on the Mechanics of Structures and Materials, Christchurch, New Zealand, 29 November–1 December 2006; pp. 817–824. [Google Scholar]
  106. Kaewunruen, S.; Remennikov, A. Laboratory measurements of dynamic properties of rail pads under incremental preload. In Proceedings of the 19th Australasian Conference on the Mechanics of Structures and Materials, Christchurch, New Zealand, 29 November–1 December 2006; pp. 319–324. [Google Scholar]
  107. Kaewunruen, S.; Remennikov, A. Post-failure mechanism and residual load-carrying capacity of railway prestressed concrete sleeper under hogging moment. In Proceedings of the International Conference on Structural Integrity and Failure 2006, Sydney, Australia, 27–29 September 2006; pp. 331–336. [Google Scholar]
  108. Kaewunruen, S.; Remennikov, A. Nonlinear finite element modelling of railway prestressed concrete sleeper. In Proceedings of the 10th East Asia-Pacific Conference on Structural Engineering and Construction, Bangkok, Thailand, 3–5 August 2006; Volume 4, pp. 323–328. [Google Scholar]
  109. Kaewunruen, S.; Remennikov, A. Rotational capacity of railway prestressed concrete sleeper under static hogging moment. In Proceedings of the 10th East Asia-Pacific Conference on Structural Engineering and Construction, Bangkok, Thailand, 3–5 August 2006; Volume 5, pp. 399–404. [Google Scholar]
  110. Remennikov, A.; Kaewunruen, S.; Ikaunieks, K. Deterioration of dynamic rail pad characteristics. In Proceedings of the Conference of Railway Engineering 2006, Melbourne, Australia, 30 April–3 May 2006; pp. 173–179. [Google Scholar]
  111. Kaewunruen, S.; Remennikov, A. Integrated field measurements and track simulations for condition assessment of railway tracks. In Proceedings of the 1st International Conference on Structural Condition Assessment, Monitoring, and Improvement, Perth, Australia, 12–14 December 2005; pp. 391–398. [Google Scholar]
  112. Kaewunruen, S.; Remennikov, A. Monitoring structural degradation of rail bearing pads in laboratory using impact excitation technique. In Proceedings of the 1st International Conference on Structural Condition Assessment, Monitoring, and Improvement, Perth, Australia, 12–14 December 2005; pp. 399–405. [Google Scholar]
  113. Kaewunruen, S. Track Pumping—A Short Term Mitigation Strategy; Technical Report No TR228; RailCorp Track Engineering: Sydney, Australia, 2014; 51p. [Google Scholar]
  114. Kaewunruen, S.; Sest, J. Inspection of Turnout Concrete Bearers for Oatlet 1098Pts; Technical Integrity Report No. TIR639; Track Services RailCorp: Sydney, NSW, Australia, 2013; 69p. [Google Scholar]
  115. Kaewunruen, S. Rail Gauge Analysis of Fastclip Heavy Duty Concrete Sleepers on a Straight Track-Illawarra; Technical Integrity Report No. TIR417; Track Services RailCorp: Sydney, NSW, Australia, 2010; 11p. [Google Scholar]
  116. Kaewunruen, S.; Daley, M. Audit of Concrete Sleepers Manufactured by ROCLA–Mittagong Factory; Technical Integrity Report No. TIR397; Track Services RailCorp: Sydney, NSW, Australia, 2010; 24p. [Google Scholar]
  117. Kerr, M.; Kaewunruen, S.; Churchill, A. Sleeper Gauge Inspection—Fastclip Medium Duty Concrete Sleepers; Technical Integrity Report No. TIR388; Track Services RailCorp: Sydney, NSW, Australia, 2010; 26p. [Google Scholar]
  118. Kaewunruen, S.; Vaughan, S. Electrical Conductivity of Concrete Turnout Bearers; Technical Report No. TR158; Track Services RailCorp: Sydney, NSW, Australia, 2009; 22p. [Google Scholar]
  119. Kaewunruen, S. Inspection for Structural Damage of Rocla 240-mm-Deep Turnout Bearers at Thirroul 324A Pt; Technical Integrity Report No. TIR338; Track Services RailCorp: Sydney, NSW, Australia, 2009; 12p. [Google Scholar]
  120. Kaewunruen, S.; Remennikov, A. Static Behaviors and Testing of Railway Prestressed Concrete Sleepers; Research Report; CRC Railway Engineering and Technology: Sydney, NSW, Australia, 2005; 61p. [Google Scholar]
  121. Kaewunruen, S.; Remennikov, A. In-Field Dynamic Testing and Measurements of Railway Tracks in Central Queensland; Research Report; CRC Railway Engineering and Technology: Sydney, NSW, Australia, 2005; 26p. [Google Scholar]
  122. Esveld, C. Modern Railway Track; The Netherlands MRT Press: Delft, The Netherlands, 2001. [Google Scholar]
  123. British Standard EN 13230-3:2009. Railway applications. Track. Concrete sleepers and bearers. Prestressed monoblock sleepers. BSI: London, UK, 2009.
  124. Fryba, L. Dynamics of Railway Bridges; Thomas Telford: London, UK, 1996. [Google Scholar]
  125. Wakui, H.; Okuda, H. A study on limit-state design for prestressed concrete sleepers. Concr. Libr. JSCE 1999, 33, 1–25. [Google Scholar]
  126. Murray, M.H.; Cai, Z. Literature Review on the Design of Railway Prestressed Concrete Sleeper; RSTA Research Report; Engineers Australia: Canberra, Australia, 1998. [Google Scholar]
  127. Gustavson, R. Structural Behaviour of Concrete Railway Sleepers. Ph.D. Thesis, Department of Structural Engineering, Chalmers University of Technology, Gothenburg, Sweden, 2002. [Google Scholar]
  128. Warner, R.F.; Rangan, B.V.; Hall, A.S.; Faulkes, K.A. Concrete Structures; Addison Wesley Longman: Melbourne, Australia, 1998. [Google Scholar]
  129. Stevens, N.J.; Dux, P.F. A Method of Designing a Concrete Railway Sleeper. Int. Patent No WO 2004/019772 A1, 4 March 2004. [Google Scholar]
  130. Obrien, E.; Dixon, A.; Sheils, E. Reinforced and Prestressed Concrete Design to EC2: The Complete Process, 2nd ed.; Spon Press: Milton Park, Oxon, UK, 2012. [Google Scholar]
  131. Indraratna, B.; Salim, W.; Rujikiatkamjorn, C. Advanced Rail Geotechnology—Ballasted Track; CRC Press: Milton Park, Oxon, UK, 2011. [Google Scholar]
  132. Leong, J.; Steffens, D.; Murray, M.H. Examination of railway track dynamic models. In Proceedings of the International Heavy Haul Conference, Kiruna, Sweden, 11–13 June 2007. [Google Scholar]
  133. Leong, J. Development of a Limit State Design Methodology for Railway Track. Master’s Thesis, Queensland University of Technology, Brisbane, Queensland, Australia, 2007. [Google Scholar]
  134. Freudenstein, S.; Haban, F. Prestressed concrete sleepers. Eur. Railw. Rev. 2006, 4, 73–79. [Google Scholar]
  135. Lutch, RH. Capacity Optimization of a Prestressed Concrete Railroad Tie. Master’s Thesis, Department of Civil and Environmental Engineering, Michigan Tech University, Houghton, MI, USA, 2009. [Google Scholar]
  136. Curić, E.; Drenić, D.; Grdić, Z. Analysis of carrying capacity of concrete sleepers for switches and crossings under static and dynamic load. Građevinar 2014, 66, 1117–1124. [Google Scholar]
  137. Kaewunruen, S.; Sussman, J.M.; Matsumoto, A. Grand Challenges in Transportation and Transit Systems. Front. Built Environ. 2016, 2, 4. [Google Scholar] [CrossRef]
  138. Kaewunruen, S.; Lee, C.K. Sustainability Challenges in Managing End-of-Life Rolling Stocks. Front. Built Environ. 2017, 3, 10. [Google Scholar] [CrossRef]
Figure 1. A real example of typical statistical data of annual wheel loading on tracks. These impact components are imposed on top of static 28-tonne axle load, which is the majority of load occurrence. Note that the allowable serviceability load can be derived from the allowable dynamic impact factor of 2.5 (prescribed). In general, the railseat load is about 70%–80% of the dynamic wheel load [125,132,133].
Figure 1. A real example of typical statistical data of annual wheel loading on tracks. These impact components are imposed on top of static 28-tonne axle load, which is the majority of load occurrence. Note that the allowable serviceability load can be derived from the allowable dynamic impact factor of 2.5 (prescribed). In general, the railseat load is about 70%–80% of the dynamic wheel load [125,132,133].
Infrastructures 02 00005 g001
Figure 2. Flowchart for limit states design of railway concrete sleepers. The concept has been adopted in Europe and Australia [39,85,134]. Capacity design check stage requires in-depth understanding of structural failure, toughness and ductility of sleepers.
Figure 2. Flowchart for limit states design of railway concrete sleepers. The concept has been adopted in Europe and Australia [39,85,134]. Capacity design check stage requires in-depth understanding of structural failure, toughness and ductility of sleepers.
Infrastructures 02 00005 g002

Share and Cite

MDPI and ACS Style

Gamage, E.K.; Kaewunruen, S.; Remennikov, A.M.; Ishida, T. Reply to Giannakos, K. Comment on: Toughness of Railroad Concrete Crossties with Holes and Web Openings. Infrastructures 2017, 2, 3. Infrastructures 2017, 2, 5. https://doi.org/10.3390/infrastructures2020005

AMA Style

Gamage EK, Kaewunruen S, Remennikov AM, Ishida T. Reply to Giannakos, K. Comment on: Toughness of Railroad Concrete Crossties with Holes and Web Openings. Infrastructures 2017, 2, 3. Infrastructures. 2017; 2(2):5. https://doi.org/10.3390/infrastructures2020005

Chicago/Turabian Style

Gamage, Erosha K., Sakdirat Kaewunruen, Alex M. Remennikov, and Tetsuya Ishida. 2017. "Reply to Giannakos, K. Comment on: Toughness of Railroad Concrete Crossties with Holes and Web Openings. Infrastructures 2017, 2, 3" Infrastructures 2, no. 2: 5. https://doi.org/10.3390/infrastructures2020005

Article Metrics

Back to TopTop