Measurements of Human Perception of Train Vibration

Round 1

Reviewer 1 Report

Interesting paper for the problem of train vibrations on buildings.

It should be highlighted whether the system proposed in Figure 6. New disc proposal was designed by the authors or otherwise. Its functioning should be explained better and in comparison with other systems if there are differences in the results.

The limits of the paper you measured in a single home; what happens if the distance from the railway line changes or if the type of construction changes. If made of brick blocks or steel frame. The type of soil and foundations should be assessed.

Expand the discussion paragraph and separate from the conclusions.

Write a new conclusions paragraph

Author Response

First of all we would like to thank you very much for your valuable comments. We did all the best to improve our manuscript:

1. 1. It should be highlighted whether the system proposed in Figure 6. New disc proposal was designed by the authors or otherwise. Its functioning should be explained better and in comparison with other systems if there are differences in the results.

   Answer:

   A new disc proposal was designed at the Cracow University of Technology by the team in which the authors of the paper were the main designers. It is now explained in the text.

    

   2. The limits of the paper you measured in a single home; what happens if the distance from the railway line changes or if the type of construction changes. If made of brick blocks or steel frame.

   Answer:

   We completely agree that the measurements on one building have limits, but there was monitoring, so there are many results. To compare results on different buildings you must remember that they will be of different structure, soil etc. The perfect situation will be when you have the same building in different locations – then you can compare the changes in the distance or the soil parameters. The different material is another challenge – but you must remember that to compare the buildings of different materials they should have the same joints, the same dimensions and should be located on the same soil. Through in-situ measurements, it is just impossible.

    

   3. Expand the discussion paragraph and separate from the conclusions.

   Answer:

   The discussion paragraph has been expanded and a separate chapter Conclusion has been added.

   4. Write a new conclusion paragraph

   Answer:

   A new conclusions paragraph has been added.

Reviewer 2 Report

The article "Measurements of Human Perception of Train Vibration" by Alicja Kowalska-Koczwara, Filip Pachla, and Tadeusz Tatara, as a contribution from Cracow University of Technology, ventures to elucidate an often overlooked aspect of environmental pollution: vibrations caused by trains and their subjective perception by humans. This comprehensive study, employing linear and non-linear regression analyses of in-situ vibration measurements, seeks to establish correlations between the train type, its speed, and the resultant perceptual impacts on residents.

A highlight of the paper is its meticulous methodology, particularly the innovative use of a measuring disk for accurate, non-invasive vibration measurements. This not only showcases the novelty of the research but also its practical implications for urban planning and environmental engineering.

However, enhancing the quality and impact of the paper could be achieved by focusing on a few areas: ensuring accuracy in the numbering of figures and tables, verifying that all references are correctly cited and accessible, expanding the discussion with comparisons to other significant research, and broadening the literature review with more recent studies. These improvements would not only bolster the paper's credibility and richness but also provide readers with a clearer understanding and broader context of the study's significance in the field.

In conclusion, this study marks a valuable contribution to understanding train-induced vibrations and their perception, with implications for building design and environmental policy. By addressing the noted enhancements, the paper could further solidify its standing as a key resource for future research in this pivotal area of urban environmental health.

Author Response

First of all we would like to thank you very much for your valuable comments. We did all the best to improve our manuscript:

1. 1. However, enhancing the quality and impact of the paper could be achieved by focusing on a few areas: ensuring accuracy in the numbering of figures and tables, verifying that all references are correctly cited and accessible, expanding the discussion with comparisons to other significant research, and broadening the literature review with more recent studies.

   ANSWER:

   The article has been checked and the numbering of figures and footnotes has been corrected.

   2. These improvements would not only bolster the paper's credibility and richness but also provide readers with a clearer understanding and broader context of the study's significance in the field.

   ANSWER:

   The improvements have been implemented in the article. These changes have improved the readability and understanding of the article in an important area of research dedicated to the effects of communication vibrations on the human body.

   3. In conclusion, this study marks a valuable contribution to understanding train-induced vibrations and their perception, with implications for building design and environmental policy. By addressing the noted enhancements, the paper could further solidify its standing as a key resource for future research in this pivotal area of urban environmental health.

   ANSWER:

   Many improvements have been introduced in the article, which in our opinion has improved its readability. The presented new version can become a basis for engineers to design buildings in such a way that communication vibrations transmitted from the ground to the buildings do not disturb the comfort of people staying in them. The article can be the basis for future research on the impact of communication vibrations on the human body.

   The literature has been supplemented and directions for further work and improvement of the methodology have been describe

Reviewer 3 Report

The authors present and discuss their work on measurements of human perception of train vibration. The topic is within the scope of Applied Sciences. The work is systematic, complete, and well-organized. The results are convincing. Some small details need to be adjusted.

Minor comments:

1. The summary of the content of the article in the abstract is not well summarized, and it is recommended that it be revised. For example, the main experimental content of this article operation is not mentioned in the abstract.

2. Figure 2 is not clear and needs to be revised.

3. The explanation of Figures 11 and 12 in the text is not detailed and specific, and it is suggested that it be revised.

4. Above Table 2, the data should preferably be described in tabular form, or the data should be presented in some other form.

5. For the summary in Table 2, where does “nearly every type of train resulted in the exceedance of the comfort level.” come from?

6. Line 265: “As can be seen from Fig. 15” should be “As can be seen from Fig. 13”

7. Errors in the formatting of documents

8. Reference 3 has errors, please revise it.

Author Response

First of all we would like to thank you very much for your valuable comments:

Minor comments:

1. The summary of the content of the article in the abstract is not well summarized, and it is recommended that it be revised. For example, the main experimental content of this article operation is not mentioned in the abstract.

ANSWER:

The abstract of the article has been changed as follows:

Environmental protection encompasses various aspects, ranging from well-known concerns like air and water pollution to landscape preservation. One often overlooked facet of pollution is the mitigation of vibrations, a matter addressed not only by Polish legislation but also by EU directives. Human perception of vibrations constitutes a subjective parameter crucial in evaluating the level of vibration pollution, influenced by factors such as age, gender, and individual height. Buildings are predominantly exposed to vibration excitation from external sources, including industrial machinery (e.g., vibration road rollers, pile driving) and transport-related sources such as roads, railways, subways, or trams. Vibrations transmitted from the ground to a building can impact its structural integrity, but more commonly, they result in discomfort for occupants. Particularly, unexpected vibrations from transport-related sources can be bothersome. This study aimed to check whether there is a correlation between the type of train and the speed of travel near a representative residential building of brick construction. The study used actual in situ measurements of horizontal components and the vertical component of vibrations in the building. Analyses of the measured vibration components were carried out to assess the impact of vibrations on people staying in the building and passively receiving these vibrations. Procedures described in the standard concerning measurements and method of analysis were used. The analyses used the value of the vibration impact index on people (WODL) by the Polish standard. The study used linear and nonlinear regression analyses to obtain information on whether there is a relationship between the type of train, its speed, and the value of the WODL index. The results of the analyses indicate a relationship between the speed of the train and the value of the WODL index, but it should be emphasized that some events deviate from the developed regression model. Adopting a multiple regression model that takes into account the speed of the train and its type gives better results. The findings aim to provide valuable information for designers and managers involved in the planning and operation of train transport systems.

2. Figure 2 is not clear and needs to be revised.

ANSWER:

The drawing has been corrected.

3. The explanation of Figures 11 and 12 in the text is not detailed and specific, and it is suggested that it be revised.

ANSWER:

We have added the following text before Figs. 11 and 12 as follows:

To illustrate the recorded vibration waveforms, the most intense horizontal components x and y, as well as the vertical component z, recorded from the passage of an old type of passenger train, were selected - see Fig. 11. In the manuscript after Fig. 10, a signal feature explanation for these components was given. The maximum value of the acceleration of the vertical z component of vibrations is particularly noteworthy. The maximum acceleration value for this component is 66.22 cm/s². The maximum acceleration values of the horizontal x and y components of vibrations are significantly smaller - see Fig. 11. Such a high value of the acceleration of the vertical z component of vibrations is due to the flexibility of the wooden ceiling structure and the distance of the building from the railway tracks. In the vertical z component of vibrations, frequencies from the 8 - 12.5 Hz band dominate - see Fig. 12. In the horizontal x component of vibrations (the x-axis is perpendicular to the railway tracks), higher components from the 40 to 63 Hz band dominate. A lower frequency band ranging from 8 to 10 Hz can also be distinguished. On the other hand, in the horizontal y component of vibrations (the y-axis is parallel to the direction of the railway tracks), dominant frequency bands of 12.5 and 40 to 63 Hz can be distinguished - see Fig. 12.

4. Above Table 2, the data should preferably be described in tabular form, or the data should be presented in some other form.

ANSWER:

Before Table 2, after the first sentence on page 11, we included an additional Table 2a containing information about the number of phenomena exceeding the threshold of vibration perception and the comfort of vibration perception.

Table 2a. Division of measured phenomena due to thresholds of vibration comfort and perception.

5. For the summary in Table 2, where does “nearly every type of train resulted in the exceedance of the comfort level.” come from?

ANSWER:

The summary in Table 2 has been corrected and the new version is as follows:

“As evident from Table 2, nearly every type of train resulted in the exceedance of the comfort level according to Polish standard [15].” 

6. Line 265: “As can be seen from Fig. 15” should be “As can be seen from Fig. 13”

ANSWER:

The sentence has been corrected and now is as follows:

“As can be seen from Fig. 13 checking the normality of the distribution it’s quite good.”

7. Errors in the formatting of documents

ANSWER:

The formatting of the manuscript has been revised and corrected. 

8. Reference 3 has errors, please revise it.

ANSWER:

The Reference No. 3 has been revised and is as follows:

“3. Khan D., Burdzik R., Measurement and analysis of transport noise and vibration: A review of techniques, case studies, and future directions, Measurement, Volume 220, 2023, 113354, ISSN 0263-2241.  https://doi.org/10.1016/j.measurement.2023.11335”

Reviewer 4 Report

The manuscript focuses on the study the relationship between the speed of the train, vibration of the floor panel of building as well as WODL. The measured data is useful for engineer to assess the vibration the building influenced by the train running nearby. However, the analysis of human perception based of the vibration of the building or train vibration were found to be insufficient so that the discussion and conclusions in the manuscript are still weak and vague.  For the methodology and approach of the measurement, map or architectural plan showing the location of the train, distance and the building should be shown. The authors should also describe how many points of measurement with justification and explanation. The signal feature should be described. Moreover, regarding the human perception, the author only used the WODL to describe the perception without conducting the questionnaire of the human response such as the level of annoying and threshold level to causing the human discomfort. I suggest that the current manuscript is rejected at this stage.  

The English can be understood.

Author Response

First of all we would like to thank you for your valuable comments and hudge effort:

1. However, the analysis of human perception based of the vibration of the building or train vibration was found to be insufficient so that the discussion and conclusions in the manuscript are still weak and vague.  

ANSWER:

In the paper, an analysis of human perception based on the measured building’s vibration was undertaken. The building was located near the train line. The location of the building relative to the railway line was described in Chapter No. 2. Detailed information about the number of measurements made, the structure of the rolling stock, and the location of the disk with measuring sensors was provided in Chapter 3.3. We note that during the 87 measurements, the passage of 7 types of trains was taken into account, from freight and passenger trains to technical trains. The location of the measuring disk is of significant importance in reliable assessments of the vibrations recorded on the human body. The location of the disk in the middle of the span of the ceiling is recommended in the Polish standard PN-B-02171:2017-06. Choosing a different location can result in an erroneous assessment of the impact of vibrations on the human body. Chapter No. 6 has been modified. Chapter No. 6 has been divided into two parts concerning discussion (Chapter No. 6) and conclusions (new Chapter No. 7). Both parts have been edited considering the reviewer’s comments.

2. For the methodology and approach of the measurement, map or architectural plan showing the location of the train, distance and the building should be shown.

ANSWER:

In Chapter 2, Figure 1a was introduced showing the location of the building concerning the railway tracks.

3. The authors should also describe how many points of measurement with justification and explanation.

ANSWER:

In Chapter 4, information about the location of the measurement point was supplemented. The measurement point was chosen in one of the residential rooms of the building with the largest area in the middle of the span. There was no need to choose multiple points due to the uniform construction of the ceiling in each of the residential rooms. In addition, the measurement point was on the side of the railway tracks.

4. The signal feature should be described.

ANSWER:

An appropriate explanation has been introduced into the text before Figure 11:To illustrate the recorded vibration waveforms, the most intense horizontal components x and y, as well as the vertical component z, recorded from the passage of an old type of passenger train, were selected - see Fig. 11. The maximum value of the acceleration of the vertical z component of vibrations is particularly noteworthy. The maximum acceleration value for this component is 66.22 cm/s². The maximum acceleration values of the horizontal x and y components of vibrations are significantly smaller - see Fig. 11. Such a high value of the acceleration of the vertical z component of vibrations is due to the flexibility of the wooden ceiling structure and the distance of the building from the railway tracks.

An appropriate explanation has been introduced into the text before Figure 12:In the vertical z component of vibrations, frequencies from the 8 - 12.5 Hz band dominate - see Fig. 12. In the horizontal x component of vibrations (the x-axis is perpendicular to the railway tracks), higher components from the 40 to 63 Hz band dominate. A lower frequency band ranging from 8 to 10 Hz can also be distinguished. On the other hand, in the horizontal y component of vibrations (the y-axis is parallel to the direction of the railway tracks), dominant frequency bands of 12.5 and 40 to 63 Hz can be distinguished - see Fig. 12.

5. Moreover, regarding the human perception, the author only used the WODL to describe the perception without conducting the questionnaire of the human response such as the level of annoying and threshold level to causing the human discomfort.

ANSWER: A survey makes sense when there is a sufficiently large number of inhabitants. two people lived in this particular apartment. WODL methodology based on RMS analysis dates back to the 1930s, when large-scale research was carried out on humans. Sensitivity thresholds have been established at a level at which it is assumed that 10% of people will feel vibrations and a comfort threshold at which as many as 90% of people will feel vibrations and this threshold cannot be exceeded

6. I suggest that the current manuscript is rejected at this stage.  

ANSWER:

We have prepared a new, improved version of the manuscript, taking into account the reviewer’s comments. We believe that this version will meet the reviewer’s expectations and will be able to be accepted for publication in the Applied Sciences journal.

Round 2

Reviewer 4 Report

It can be accepted after a large modification on the paper.

It can be accepted after a large modification on the paper.