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Academic Editor

PLOS One

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

Reviewer #1: Yes

Reviewer #2: Yes

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2. Has the statistical analysis been performed appropriately and rigorously? -->?>

Reviewer #1: Yes

Reviewer #2: Yes

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3. Have the authors made all data underlying the findings in their manuscript fully available??>

The PLOS Data policy

Reviewer #1: Yes

Reviewer #2: Yes

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4. Is the manuscript presented in an intelligible fashion and written in standard English??>

Reviewer #1: Yes

Reviewer #2: Yes

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Reviewer #1: The manuscript presents a semantic segmentation and quantitative analysis framework based on TransUNet for tunnel lining crack and water leakage detection. The study has certain engineering application value, and the overall manuscript is well organized, with a relatively clear experimental workflow and intuitive presentation of results. In particular, the integration of geometric quantitative analysis with engineering validation enhances the practical significance of the study. However, from the perspectives of manuscript standardization and academic presentation, several issues remain regarding language expression, experimental analysis, literature review, and discussion of results. The manuscript is recommended for further revision and improvement. Specific comments are as follows:

1.The manuscript contains several terminology inaccuracies as well as inconsistencies between British and American English usage. The authors are encouraged to carefully proofread the manuscript and unify the writing style throughout. For example:

a)On Page 7, Line 157, “Attenuated Spatial Pyramid Pooling (ASPP)” is incorrect and should be revised to “Atrous Spatial Pyramid Pooling (ASPP)”;

b)Terms such as “lesion,” “pathologies,” and “disease types,” which are more commonly used in medical imaging literature, appear throughout the manuscript and may result from direct translation. It is recommended to replace them with terminology more appropriate for civil engineering contexts, such as “defect types,” “distress categories,” or “tunnel defects”;

c)British and American English spellings are mixed in the manuscript, such as “modelling/modeling” and “whilst/while.” A consistent language style should be adopted;

d)In Fig. 1 and Fig. 2, the term “masked images” is not sufficiently precise and is recommended to be replaced with “ground-truth masks” or “annotation masks.”

2.Although the literature review is generally comprehensive, it remains largely focused on conventional CNN-based approaches, while the discussion of recent Transformer-based methods for infrastructure defect detection is relatively limited. It is recommended that the authors further incorporate recent studies, such as: Applications of SegFormer in infrastructure defect detection; Fine-grained crack segmentation models such as CrackFormer and CrackSegFormer; Research related to lightweight Transformer architectures and boundary enhancement strategies.

3.In the water leakage detection task, U-Net achieves better F1-score and IoU values than TransUNet. However, the manuscript repeatedly emphasizes that TransUNet demonstrates the best overall performance. It is recommended that the authors present the experimental findings in a more objective and balanced manner. For example: Emphasize the advantages of TransUNet in terms of Precision and boundary integrity; At the same time, acknowledge that U-Net demonstrates superior region overlap and overall balanced performance. In addition, overly absolute expressions such as “significantly outperforms” and “best overall performance” should be used more cautiously to improve the credibility and rigor of the discussion.

4.The description of the dataset annotation procedure is relatively brief. It is recommended that the authors provide additional details regarding: Annotation tools and annotation workflow; Annotator information and annotation principles; Whether manual verification and correction were performed. Furthermore, the acquisition process of the Ground Truth data should be clarified.

5.In the crack length calculation formula around Line 196, only the mathematical expression is currently provided, while the physical meanings of the variables and symbols are not sufficiently explained. It is recommended that the authors provide additional clarification regarding the definitions of the variables and the corresponding calculation process to improve readability and completeness.

Reviewer #2: The paper investigates tunnel lining crack and water leakage detection based on a TransUNet semantic segmentation framework and further conducts quantitative analysis of defect geometry. The topic is relevant to intelligent tunnel inspection and infrastructure maintenance, and the study demonstrates practical engineering relevance. The manuscript is generally well organized, and the experimental workflow is clearly presented. In particular, the integration of semantic segmentation with quantitative defect measurement improves the practical applicability of the proposed framework. There are some comments.

1. The manuscript mentions that both public datasets and engineering field images were adopted; however, important information regarding the dataset composition remains insufficiently described. In particular, the proportions of different data sources, annotation procedures, and dataset construction details are not clearly presented. Additional information regarding dataset preparation and annotation is needed to improve the reliability and reproducibility of the study.

2. The experimental evaluation is mainly based on metrics such as Precision, Recall, F1-score, and IoU. While these indicators are commonly used in semantic segmentation tasks, the statistical analysis of the experimental results is still relatively limited. It would be beneficial to further provide: mean and standard deviation (std) obtained from repeated experiments; error distribution analysis; boxplots or error distribution visualizations.

3. Currently, crack length, crack width, and water leakage area are all quantified in pixel units, while the correspondence between image-space measurements and real-world engineering dimensions has not been sufficiently explained. Further clarification regarding the relationship between pixel-scale measurements and actual physical dimensions is recommended to strengthen the engineering applicability of the proposed framework.

4. The manuscript performs quantitative analysis of crack length, crack width, and leakage area, which represents a valuable engineering-oriented contribution. However, the current crack width estimation method is based on the average width calculated from crack area and length, which may have limited applicability for complex cracks with highly non-uniform widths. It is recommended to discuss the limitations of this approach in the Discussion section. In addition, more advanced width estimation methods, such as local normal-direction width measurement and sub-pixel boundary extraction, could be suggested in the future work section to further improve the reliability of engineering measurements.

5. The overall language quality of the manuscript is generally acceptable; however, some sentences are relatively lengthy and may affect readability. The manuscript would benefit from further revision with respect to: English grammar and sentence structure; consistency of tense usage; consistency and standardization of technical terminology.

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what does this mean?). If published, this will include your full peer review and any attached files.

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Reviewer #1: No

Reviewer #2: No

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To ensure your figures meet our technical requirements, please review our figure guidelines: https://journals.plos.org/plosone/s/figures

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Semantic Segmentation and Quantitative Analysis of Tunnel Cracks and Water Leakage Using a TransUNet Framework

PONE-D-26-20664R1

Dear Dr. Yu,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

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Kind regards,

Baohua Guo

Academic Editor

PLOS One

Additional Editor Comments (optional):

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

Reviewer #1: All comments have been addressed

Reviewer #2: All comments have been addressed

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2. Is the manuscript technically sound, and do the data support the conclusions??>

Reviewer #1: Yes

Reviewer #2: Yes

**********

3. Has the statistical analysis been performed appropriately and rigorously? -->?>

Reviewer #1: Yes

Reviewer #2: Yes

**********

4. Have the authors made all data underlying the findings in their manuscript fully available??>

The PLOS Data policy

Reviewer #1: Yes

Reviewer #2: Yes

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5. Is the manuscript presented in an intelligible fashion and written in standard English??>

Reviewer #1: Yes

Reviewer #2: Yes

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Reviewer #1: Thanks for your revision, I think the quality of the manuscript has been improved and can be accpeted now

Reviewer #2: The author has made significant revisions and improvements to the paper based on feedback. I suggest accepting this paper.

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what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review?  For information about this choice, including consent withdrawal, please see our Privacy Policy

Reviewer #1: Yes:  Gen Li

Reviewer #2: No

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