Full-Scale Train Derailment Testing and Analysis of Post-Derailment Behavior of Casting Bogie

Round 1

Reviewer 1 Report

The paper describe the main evidences of two experimental tests related on
a full-scale train bogie derailment. In particular, have been analyzed in depth
the effects of the post-derailment behaviour.
The experimental setup has been prepared very carefully and, for this reason,
the results seem very reasonable. Moreover, the paper is well written and organized.
The paper is certainly advisable for a possible pubblication in this journal.
Two minor issues are listed below.

1) Figure 2: the the left images are of poor quality. Try to improve the definition
and insert same indications (written and arrows) to make the figure more easily and
quickly understandable.

2) par. 2.1.: what is the difference between acceleration, test and breaking regions?
Maybe a better description could be introduced.

Author Response

Response to Reviewer 1 Comments

 

The authors would like to convey their appreciation to the reviewer for the valuable comments made by the reviewer. The authors have revised the paper based on the reviewers’ comments. Revisions made to specific comments are presented below. All modified and additional phrase have been written in red in this revised manuscript.

 

Point 1: The paper describe the main evidences of two experimental tests related on a full-scale train bogie derailment. In particular, have been analyzed in depth the effects of the post-derailment behaviour. The experimental setup has been prepared very carefully and, for this reason, the results seem very reasonable. Moreover, the paper is well written and organized. The paper is certainly advisable for a possible publication in this journal. Two minor issues are listed below.

 

Figure 2: the the left images are of poor quality. Try to improve the definition and insert same indications (written and arrows) to make the figure more easily and quickly understandable.

 

Response 1: First of all, thank you for taking time to review the submitted paper. Regarding Fig. 2, the authors have revised the figures to have high definition and to make the figure more easily understandable, as pointed by the reviewer. Please, refer revised Fig. 2 in the revised paper.

 

Point 2: par. 2.1.: what is the difference between acceleration, test and breaking regions? Maybe a better description could be introduced.

 

Response 2: Acceleration region represents the region to obtain the target speed of the bogie where test bogie is released at the end of the acceleration region. The test bogie is derailed at the start point of test region and the post-derailment behavior is observed in the test region. Breaking region is provided at the end of test region. It is a margin region to provide the safety from the unexpected behavior of derailed bogie or train.

The authors have added above definitions for the acceleration, test and breaking region in the revised paper. Please, refer line 73-77 in the revised paper.

Author Response File: Author Response.pdf

Reviewer 2 Report

Dear Authors,

Thank you for the exciting contribution to the field of railways safety improvement. 

The paper presents a technical report on a specific experiment based on two samples only. The description of the experimental setup as well as results analysis is done correctly.

Unfortunately, the paper lacks several elements characteristic of a scientific paper.

Literature analysis does not exist. There is no reference to similar research or standard testing methods. No examples from other researchers are presented. Consequently, in the analysis part and conclusions, you included no comparative analysis which might underline the novelty of your solution. It is unclear if the presented methodology allows extrapolating the results to other railway systems like bogies, carriages, etc. The paper describes the behaviour of a particular bogie running at two different speeds, but the reader does not know if the response is representative. The authors did not mention, if there was any difference when the bogies were attached to a carriage (passenger, cargo, ...). Section 4 repeats the results from section 3. The scientific paper must include more universal conclusions. Sentences like "The proposed methodologies may be helpful to researchers planning train derailment tests" are insufficient and superficial. If I were a researcher, the paper would have limited significance for me. It would tell me only that someone had done two test runs of a bogie. The Authors did not discuss the advantages and drawbacks of the presented methodology.

Therefore I rejected your paper in present appearance. However, it has the potential for further development in the future.

With regards

Your reviewer.

Author Response

Response to Reviewer 2 Comments

 

The authors would like to convey their appreciation to the reviewer for the valuable comments made by the reviewer. The authors have revised the paper based on the reviewers’ comments. Revisions made to specific comments are presented below. All modified and additional phrase have been written in red in this revised manuscript.

 

Point 1: Dear Authors,

Thank you for the exciting contribution to the field of railways safety improvement.

The paper presents a technical report on a specific experiment based on two samples only. The description of the experimental setup as well as results analysis is done correctly.

Unfortunately, the paper lacks several elements characteristic of a scientific paper.

Literature analysis does not exist. There is no reference to similar research or standard testing methods. No examples from other researchers are presented. Consequently, in the analysis part and conclusions, you included no comparative analysis which might underline the novelty of your solution. 


 

Response 1: First of all, thank you for taking time to review the submitted paper. Regarding the literature review, the most of previous researches are about the ‘simulation of post-derailment analysis’ and these researches were mentioned in the submitted paper [Ref. 2-4, 9-13 in the submitted paper]. In the case of ‘derailment test’, only few researches conducted in China [Ref. 14 in the submitted paper] can be found in the publication domains. Their test [Ref. 14 in the submitted paper] was conducted in the laboratory and the speed was very slow (16km/h). Therefore, it should be noted that the results of real scale derailment test (Not real scale collision test) was very limited and the focus was made on the ‘proposal of field test methodologies for full scale train derailment experiment’ in this study.

 The authors believe that the proposed methodologies are general for the other derailment test. It would be appreciated if the reviewer understands this situation.

 

Point 2: It is unclear if the presented methodology allows extrapolating the results to other railway systems like bogies, carriages, etc. The paper describes the behaviour of a particular bogie running at two different speeds, but the reader does not know if the response is representative. The authors did not mention, if there was any difference when the bogies were attached to a carriage (passenger, cargo, ...).

 

Response 2: In this study, the focus was made on the ‘derailment test methodologies’. The acceleration and release method of test bogie or train is proposed. Also, the derailment device and data acquisition method were proposed. These methods are general and can be extrapolated to other railway system.

 In the case of post-derailment behavior analysis, only two cases were considered in this study, as pointed by the reviewers. The authors have intended to show that the proposed methodologies are applicable to the derailment test by full scale derailment test of casting bogie as an example. Also, the post-derailment behaviors of casting bogie were analyzed. Since tests were limited to casting bogie, the title of the revised paper was modified as ‘Full-Scale Train Derailment Testing and Analysis of Post-Derailment Behavior of Casting Bogie’ to clearly reflect the contents of the submitted paper. Please, refer line 2-3 in the revised paper.

 

Point 3: Section 4 repeats the results from section 3. The scientific paper must include more universal conclusions. Sentences like "The proposed methodologies may be helpful to researchers planning train derailment tests" are insufficient and superficial. If I were a researcher, the paper would have limited significance for me. It would tell me only that someone had done two test runs of a bogie. The Authors did not discuss the advantages and drawbacks of the presented methodology.

Therefore I rejected your paper in present appearance. However, it has the potential for further development in the future.

 

Response 3: As mentioned in previous answer, the proposed methodologies are generally applicable to other train derailment test. Thus, the conclusions were revised clearly to deliver the significance of the present work (Please, refer line 327 in the revised paper). It should be noted that the derailment test for freight train is conducting by using the proposed method recently and it is successful up to now.

It would be very appreciated if you reconsider the submitted paper by considering the answers mentioned in this response to the reviewer’s comments.

Author Response File: Author Response.pdf

Reviewer 3 Report

The frequency range of the used instrumentation should be reported.

Author Response

Response to Reviewer 3 Comments

 

The authors would like to convey their appreciation to the reviewer for the valuable comments made by the reviewer. The authors have revised the paper based on the reviewers’ comments. Revisions made to specific comments are presented below. All modified and additional phrase have been written in red in this revised manuscript.

 

Point 1: The frequency range of the used instrumentation should be reported. 


 

Response 1: Thank you for taking time to review the submitted paper. As pointed by the reviewer, the authors have added the frequency range of the used instrumentation in the revised paper. Please, refer line 129-131 in the revised paper.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Dear Authors,

Thank you for your explanations and effort put into the improvement of the paper.

Best regards

Author Response

Response to Reviewer 2 Comments

Point 1: Dear Authors,

Thank you for your explanations and effort put into the improvement of the paper.

Best regards 


Response 1:
Once again, thank you very much for taking time to review the submitted paper.

 

Author Response File: Author Response.docx