Predictive Analysis of Corrosion Dynamics in Prestressed Concrete Exposed to Chloride Environments

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This paper investigates the corrosion behavior of 5mm diameter wires in prestressed concrete beams under marine chloride attack. It reveals the impact of concrete strength on structural integrity at different stress levels and corrosion rates. The study provides a detailed analysis of corrosion behavior using advanced Digital Image Correlation (DIC) technology and machine learning prediction models. Although the research includes extensive experiments and analyses, some revisions are necessary before publication:

 

1. The paper's background and introduction sections fail to clearly articulate the necessity of studying small diameter prestressing tendons and do not explain the choice of 5mm diameter.

 

2. Additionally, there is no mention of the advancements in Digital Image Correlation (DIC) technology and machine learning in these sections. The methods section should emphasize the methodology and research approach rather than extensively elaborating on the research background and significance. There are only 16 references cited throughout the paper; more recent literatures that are highly relevant to the presented study should be mentioned and discussed, such as

Mechanical–transport–chemical modeling of electrochemical repair methods for corrosion-induced cracking in marine concrete.

Prediction of chloride diffusivity in concrete using artificial neural network: modelling and performance evaluation.

 

3. While the paper presents experimental results, it lacks in-depth analysis of these results. For instance, the analyses of figures 11 and 12 are insufficient. Figure 12 only displays data for 68MPa, without a comprehensive listing of experimental results.

 

4. The conclusion section, although enumerating the experimental conclusions, does not clearly specify which parts of the experiments produced the corresponding data. For example, the paper does not provide specific formulas or methods for calculating the strain ratio.

 

5. The summary section still contains excessive background information. It should succinctly summarize the study's conclusions, explaining how they guide future research and applications. Furthermore, it should clearly outline specific directions for future research rather than offering vague statements.

 

Author Response

attached

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

 

In this manuscript the authors claim studying the corrosion behavior of 5 mm prestressed wires in concrete beams under marine chloride attack. The authors claim that the marine chloride attack was simulated.  

C1) It is not very clear if the authors make the difference between the corossion produced by chlorides only and the chemical action of the seawater which contains additional ions like Mg, K, Ca and SO4. The oxygen present in the atmospheric air and in seawater, either as entraped air or dissolved, has an essential role in corrosion of steel in the marine environment. There are additional factors like marine organism, temperature, hydrostatic pressure, tidal action which play in important role in the marine aggression on concrete members. Therefore, it is doubtful if the lab conditions created by authors really simulates the aggression of the marine environment.

 

C2) In Introduction the authors included many corrosion cases for concrete members but they are related to the post-tensioned members not to pretensioned members as it are presented into the study. The practice says that more many cases have been recorded so far to post-tensioned versus pretensioned.

 

C3) The bending test is unnecessary and unsatisfactory. The authors should know what is the difference between a beam model in bending versus in shear. The size and proportions of the beam model are close to a model in shear because the ratio a/d is much smaller than five where the "a" is the shear span, that is the distance from applied force to the support, and "d" is the relative depth of the reinforcement. Typically to get a model sensitive only to bending  the ratio a/d should be larger then 5. Furthermore, the prestressed members are slender members where the span to height ratio is high compared to reinforced concrete members, a ratio over 20.

C4) It is not very clear if the model was taken up to the failure. If yes, then what are the failure modes?

C5) There is no cross section presented in order to identify the number of wires or strands and their position.

C6)The authors should remove from the text the excessive words (pompous) like "valuable insights", "significant advancements", "profound impact", "vital" "significantly enhancing", "crucially included", "pivotal part", holistic approach, etc.

C7) The Figure 9 is not explained and commented. What is the meaning of the presented figures on the beam. The capture of the figure is not well explanatory

C8) The Figure 10 is not explained and commented. What is the meaning of the presented figures on the beam. The capture of the figure is not well explanatory.

C9) The statistical and machine learning analysis is very confused, unexplanatory. The connection with the experimental part is very poor. It must be restructured or better removed from the manuscript.

C10) The discussion section, heading 6, is completely unsatisfactory and it must be replaced .

C11) The conclusion section, heading 7, is completely unsatisfactory and it must be replaced. There is no conclusions there. It contains only phrases already encountered in the text.

The manuscript in this shape is to be rejected. The authors must make a serious revision of the manuscript. The authors should change the title, too.

Comments on the Quality of English Language

Moderate editing of English language required

Author Response

attached

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The article deals with the study of a very interesting and important topic from the point of view of construction safety.The research program is planned correctly. However, the article needs improvement so that it meets the requirements of the journal and is easy for readers to read. My comments are as follows:

1. The letters in Figure 1 are too small, this drawing is illegible, it should be corrected.

2. What do you mean writing "specific and unit weight"? The specific weight, is also known as the unit weight – this is the same parameter. This is a volume-specific quantity defined as the weight per unit volume of a material. In the next sentence you write about “specific mass”. Unify the nomenclature, it creates confusion.

3. What is the tensile strength of the wire – in line 198 is information that this property is equal 1860MPa, on the figure 2 there is information that this property is equal 1.860MPa This is confusing probably because of the separatior that you want to use on figure so it should be 1,860MPa but also you should use this separator in the text. I advise you not to use the separator separating thousands of "," unless the editors introduce it uniformly throughout the text.

4. Leters on figure 2 are to big and the  information about what means red linie please give in the caption of the figure.

5. In Table 1, in the description of the samples, instead of commas, give periods as you did in the rest of the paper

6. Give information about numerical results in the abstract.

7. The discussion and conclusion sections are the same 4 very general paragraphs. The article was probably written in a hurry. With so many authors, such a mistake should not happen. It gives the impression of a lack of professionalism.

8. There is a lack of discussion.

9. And what is in the conclusions is too general. These paragraphs can stay here but this section should be improved.

10. Too little literature review. There are only two papers after 2021 cited.

 

Author Response

attached

Author Response File: Author Response.pdf

Reviewer 4 Report

Comments and Suggestions for Authors

Comments on the paper submitted to Infrastructures (ISSN 2412-3811):

Title: Understanding Corrosion Dynamics: A Predictive Analysis of Corrosion in Marine-Exposed Prestressed Concrete

Manuscript ID: infrastructures-3101699

General Comments

In general, the paper is well-structured as it clearly provides the context, motivation, purpose, methods, and results. Besides, the results have the potential to impact the design and monitoring of marine infrastructures and may be of interest to both practitioners and researchers on prestressed structures. Nevertheless, I identified some minor corrections that the authors should consider before the paper be considered for publication.

Based on this, my recommendation is to accept with minor revisions required.

1 – In the sentence “It simulated aggressive chloride environments to understand the impact on structural integrity and longevity.”. This sentence does not sound clear. Please avoid sentences starting with “It” when replacing the subject and reword such sentences.

2 – In the sentences like “this research has the potential to significantly impact the safety”. Consider changing the wording to “this research can significantly impact the safety

3 – In some cases, consider replacing “longevity” with “service life”. “service life” seems to be the most appropriate technical term.

4 – The introduction is well-structured. Besides, the text is written in good English.

5 – I missed some mention to a most recent collapse such as the “Morandi Bridge Italy collapse” due to corrosion of prestressing wires. Consider adding some comment on this.

6 – “Target compressive strength” and “measured compressive strength” may be very different in practical cases. In the sentence “Two concrete mixes were prepared targeting compressive strengths of 32 MPa and 68 MPa.”… the authors are referring to the measured properties or target properties? In research, we are more interested in using the measured properties in structural analyses…

7 – The paper has two “Table 1”. Please, correct the subtitle of the second Table.

8 – In Table 2, how was the chloride Cl-concentration controlled for concrete? Please, clarify

9 – Line 284, consider replacing " detailed deformation map” with “detailed strain distribution pattern”.

10 – Lines 289 to 291 seems to have duplicated information compared to the previous paragraph “Lines 279 ti 284”. Please, correct this paragraph.

Conclusions: The conclusions are supported by the presented methods and results. Besides, they are valuable for future investigations in this field.

English writing:

The paper was written at a good English level. Minor revisions on this aspect are required.

Figures and tables.

Most Figures were well prepared.

Comments on the Quality of English Language

The paper was written at a good English level. Minor revisions on this aspect are required.

Author Response

attached

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The authors have made a good effort to address the comments. The reviewer is happy to recommend it for publication.

 

Author Response

Thank you for taking the time to review our manuscript. 

Reviewer 2 Report

Comments and Suggestions for Authors

The authors has improved in some extent the manuscript.

The Discussion and Conclusion part remains unsatisfactory presented.

Clear and substantial conclusions must be formulated.

Comments on the Quality of English Language

Moderate editing of English language required.

Author Response

Thank you for taking the time to review our manuscript. Kindly find the attached document. 

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors The authors corrected the article. It meets the requirements for publication.

 

Author Response

Thank you for taking the time to review our manuscript.