Experimental–Numerical Analysis on the Cable Vibration Behavior of a Long-Span Rail-Cum-Road Cable-Stayed Bridge under the Action of High-Speed Trains
Round 1
Reviewer 1 Report
Dear Authors,
Thank you for presenting this study that offers valuable insights about cable vibration behavior analysis carried out on a long-span rail-cum-road cable-stayed bridge under the action of high-speed trains.
Please find below my recommendations about the work.
General Comments
Two sections should be added and worked on in the context of the present paper:
1. First, a "Methods and Materials (Methodology)" section, where you should explain what procedures, approaches, designs, and treatments you have carried out in the research. This section will allow other researchers to replicate the studies and understand the linearity between the approach of the objectives and the results obtained.
2. And, before the "Conclusions" section, it would be expected to be a "Discussion" section, where you could generate further discussions about the obtained results and compare/discuss them against previous research/case studies to validate your findings.
Abstract
It is recommended to revise the abstract to address the following comments:
3. Line 12: "widely used" is suggested rather than "widely built."
4. Line 13: Is "it vital to understand the vibration" for who/what purpose? Please explain the motivation.
5. Line 15: Is it verified by whom and how?
6. Line 19: "accurately simulate." What does it mean "accurately"? Please quantify the accuracy of the simulation.
7. Line 21: "approximate to", please quantify it.
1. Introduction
The introduction should be further developed/extended. Please see some points to be addressed:
8. Please add further detail about rail-cum-road cable-stayed bridge, with more bibliographical review.
9. Please add further detail about traditional highway or rail-way cable-stayed bridges and highlight the main differences between the advantages and disadvantages of the "rail-cum-road cable-stayed bridge."
10. Please add further discussions about bridge types, vibration studies, FE solutions, and numerical models, with references to other authors.
11. Please connect the last paragraph of the introduction (Lines 45 to 52) to the paper section organization. The reader should know what he will find in the paper and how it is organized. For instance, "First, a numerical solution program …" is presented in section X, then, in section Y, it is discussed …
2. Analysis of cable vibration under double-end excitation
12. Please add an introduction to this section, explaining in advance how it is organized and what will be developed in each sub-sections 2.1 and 2.2.
13. Line 65: Please explain why "The bending and torsional stiffness of the cable are ignored."
14. Line 67: Please explain why "The stress of cable is always within the elastic limit."
15. Figure 2 (a) and (b) are equal. You do not need to present it twice if there is no difference between them.
16. Line 72: Please add a bibliographical reference from where we can find further information about "D'Alembert's principle."
17. Line 72: Please add a bibliographical reference from where we can find further information about "D'Alembert's principle."
18. Line 104: Please add a bibliographical reference from where we can find further information about the "Galerkin method."
19. Line 106: Please explain why you are ignoring the damping of the cable.
20. Line 114: Please explain and justify adopting "link180 elements in ANSYS software".
21. Line 114: Please add the reference to "form-finding analysis" and explain it.
22. Lines 117-118: Please refer to "linear perturbation analysis with prestress" and explain it.
23. Line 122: Explain why only the first four model frequencies were evaluated.
3. Numerical simulation of the rail-cum-road cable-stayed bridge
24. The first paragraph, Lines 126 to 135, should be further detailed. Is it a real or hypothetical example/case? If it is real, please provide further information.
25. Lines 137-138: This statement, "The long-span rail-cum-road cable-stayed bridge is subjected to the combined action of wind, trains, vehicles, and environmental temperatures during the operation period," should be referenced to someone (previous research).
26. Lines 144-145: Please explain and justify adopting BEAM188, SHELL181, and LINK180 elements in ANSYS software.
27. Lines 146-147, please, provide further information about the FE mesh and the analysis convergency adopted criteria.
4. The dynamic behavior of the cable under the action of the train
28. Line 195: Please add a bibliographical reference from where we can find further information about the "moving load method" and explain it.
29. Line 197: Please, add a bibliographical reference from where we can find further information about "CRH3 electric multiple units (EMU)".
5. Vibration analysis of the cable under the double-end excitation
30. Adding the main pieces of the programming code used to model the problem and solve it in MATLAB is recommended.
31. Lines 246-247: Explain why and based on what the first six-order vibration of the cable is accurate enough.
6. Conclusions
32. Line 258: Please, quantify "accurate FEM."
33. Line 268: Please, quantify "agrees well."
34. Lines 269-271: "In practical applications, the numerical model is simpler to use than the finite element model and can quickly calculate the vibration response of any position of the cable;" it should be tested in more cases, including in no symmetrical bridge structures before reaching such broad comment.
35. Line 280: Please indicate which velocities (in numbers) you are referring to.
36. Finally, please add the limitations of the present work and recommendations for further studies.
I hope to have helped with the recommendations above, and I look forward to your answer.
Best regards,
The Reviewer
Author Response
Please see the attachment.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
· Table 1- the four modal frequencies –errors between In-plane and Out of Plane are similar.
Is this phenomena same for long span and different diameters of cables?
· Effect of boundary conditions on behavior during the vibrations – needed more clarifications
· Conclusion :
Under the action of the high-speed train, the displacement and acceleration ampli-tude of the cable near the train load side are larger;
Why?
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 3 Report
The paper numerically (by FE model in ANSYS) studied a rail-cum-road cable-stayed bridge. The paper is good. The revision:
1) Please add a notation list.
2) In order to provide a more comprehensive literature review, the authors should cite and discuss the following relevant papers in their revised manuscript. The paper numerically , by finite element method (FEM-ANSYS), investigated the connections.
Nassiraei, H., Zhu, L. and Gu, C., 2021. Static capacity of collar plate reinforced tubular X-connections subjected to compressive loading: study of geometrical effects and parametric formulation. Ships and Offshore Structures, 16(1), pp.54-69.
3) Please add the sensitive analyze on the mesh size in FE modeling.
4) Figs. 9b and 10 need more discussion in the text.
5) please more discus in the text on the “the displacement and acceleration amplitude of the cable near the train load side are larger”
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 4 Report
The paper presents a Fusion Analysis on the Cable Vibration Behavior of a Long-span Rail-cum-Road Cable-stayed Bridge under the Action of High-speed Trains. This paper focuses on the cable’s dynamic response behaviour of a long-span rail-cum-road cable-stayed bridge under the train loads. There are many flaws in the present form of the manuscript which are needed to be addressed properly. My minor revision concern is related to the introduction, results and discussion
1. Motivation of the research significant is not reported
2. Problem statement should be more extended in the abstract and introduction sections.
3. The methodology of this study is not clear, you may use a flow chart to describe the main steps you used to perform this analysis.
4. The limitations and scope of this study should be addressed.
5. Many literature review is missing from the introduction. The literature review does not give valid credit on the research gap. There are several research have been adopted on the study of analysis on the cable vibration
6. Can you validate the current results with the literature review studies,
7. The results of the models are nearly identical. What is the advantages to report several models? you need to give a valid justification for that. Compare with the literature.
8. The manuscript is associated with several technical problems. You need to read the content more carefully and resolve the clearance of the sentences.
9. Give a limitation and possible future research.
10. Give the practical implementation for design.
11. Proofreading is required for this article.
Please kindly make revision on the language of the paper presentation. There are some minor typos and grammatical errors.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 5 Report
The reviewer thanks the authors for their contribution. In general, the numerical work is appreciated because the findings are useful information for bridge assessment applications. Nonetheless, the goal of the work must be better explained within Abstract, Introduction and Conclusions. Furthermore, the publication in the “Applied Sciences, MDPI” is not recommended unless the following suggestions are taken into account:
1) The title of the article is “Fusion Analysis on the Cable Vibration Behavior of a Long-span Rail-cum-Road Cable-stayed Bridge under the Action of High-speed Trains”. What do the authors mean with “fusion” ? Please revise the title.
2) Introduction. The current state of knowledge relating to the topics of the article has not been covered and clearly presented, and the authors’ contributions and findings are not emphasized. In this regard, the authors should make their effort to address these issues.
3) Introduction. The authors have focused on the determination and measurement of the fundamental frequency of slender cables. An accurate value of the fundamental frequency is a proper indicator for axial load estimation in steel beams, bridge cables and hangers. Please refer to this issue through the following references:
- https://doi.org/10.1016/j.engstruct.2018.03.070
- https://doi.org/10.1016/j.jcsr.2023.107854
4) Section 2. The authors have neglected the bending stiffness of the bridge cable under vibrations. This could be done for slender cables only. It is strongly suggested that the authors should consider a set of no-slender cables in which the bending stiffness cannot be ignored. In this case, no-slender cables must be simulated as beam members. Please simulate this behavior by ANSYS finite element and MATLAB code analyses to combine the existing results.
5) Table 1. Percentage comparison errors must be reported with one decimal only.
6) The geometric and mechanical characteristics of the bridges, which have been considered, have not clearly been illustrated. Please provide more information and introduce figures with schemes of the bridges.
7) Please cite the software ANSYS and MATLAB, which have been used, in the references.
8) Please insert tables which list the types of finite element used, with the corresponding amounts within the finite element models and mesh sizes of the bridges.
9) Section 4. Please show the corresponding combinations of the live loads (traffic, trucks etc.) assumed in the nonlinear finite element analyses.
10) Please underline the boundary conditions of the slender steel cables which have been analyzed in the work.
11) The authors have mentioned that nonlinear geometrical effects have been considered within the analyses. How have they been specifically considered along the cables in the finite element models ? Please specify.
12) Please specify the units of dimensions in Figure 4.
13) Section 4. “The bridge had equipped a structural health monitoring (SHM) system, and the data recorded by the displacement sensors and acceleration sensors installed at the midspan of the main span near the downstream side can be used to verify the accuracy of the FEM”. Please provide more information on the field SHM system which has been considered (characteristics and locations of the devices, frequency of the recorded data, figures and schemes of the bridge under investigation etc.).
14) In Figure 8, monitoring and numerical data have been compared. Please insert a table/s in which the comparison percentage errors are underlined, as have been done in Table 1.
15) The further work should be mentioned at the end of the article. Please mention.
16) Additional comments should be added in regard to the practical value of this work, and how the industry can profit from this article. Are the authors intended to develop some nondestructive methods for SHM and assessment of bridge cables ?
17) The English should be checked and improved. Please also check the grammar. It is suggested that the authors should ask a native speaker in English to edit the whole article.
English language requires an extensive editing.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Dear Authors,
Thank you for sending a revised version of the manuscript addressing my comments.
Best regards,
The Reviewer
Author Response
Dear Reviewer,
Thank you so much for giving us helpful suggestions, which helped us improve our manuscript.
Best regards,
The Authors
Reviewer 3 Report
Ready to publish.
Author Response
Dear Reviewer,
Thank you so much for giving us helpful suggestions, which helped us improve our manuscript.
Best regards,
The Authors
Reviewer 5 Report
I suggest the following title for the article: "Experimental–Numerical Analysis on the Cable Vibration of a Long-Span Rail-Cum-Road Cable-Stayed Bridge under the Action of High-Speed Trains". Please also underline in the abstract, introduction and conclusions that the bending stiffness of the cables under investigation has been neglected.
English language requires a moderate editing.
Author Response
Dear Reviewer,
Thank you so much for giving us helpful suggestions, which helped us improve our manuscript.
So that you know – the title has been revised according to your suggestion.
Neglecting the bending stiffness is underlined in the abstract, introduction, and conclusions sections, highlighted in blue in the revised manuscript.
A proficient researcher with a strong English writing command thoroughly checks the grammar and spelling. The text is error-free and precisely crafted to meet your standards.
Best regards,
The authors
