Induced Partial Saturation: From Mechanical Principles to Engineering Design of an Innovative and Eco-Friendly Countermeasure against Earthquake-Induced Soil Liquefaction

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

geosciences-2982828-review

Induced Partial Saturation: from mechanical principles to engineering design of an innovative and eco-friendly countermeasure against earthquake-induced soil liquefaction

This is an interesting and valuable review paper. Some revision suggestion as follow:

1. What are the meanings of PWP and GW in Figure 1a? It is recommended not to use abbreviations.

2. What are the meanings of IPS in Figure 2? It is recommended not to use abbreviations. Can we consider merging Figure 1 and Figure 2.

3. Some formulas lack specific explanations for the meaning of letters, which should be checked and supplemented completely.

4. The gas name symbol in Figure 4 should be modified to subscript.

5. The clarity of some cited images is relatively low.

Comments on the Quality of English Language

Moderate editing of English language required

Author Response

We appreciate the work of all reviewers, necessary to improve the manuscript. We are grateful to them. In the following we reported our replies and the modified version of the manuscript.

This is an interesting and valuable review paper. Some revision suggestion as follow:

1. What are the meanings of PWP and GW in Figure 1a? It is recommended not to use abbreviations.

Thank you for your comments. We reported the meaning in the caption of Figure.

2. What are the meanings of IPS in Figure 2? It is recommended not to use abbreviations. Can we consider merging Figure 1 and Figure 2.

Thank you. We added the explanation of IPS in the text (line 128). Regarding the merge of Figure, we decided to maintain the current version to make clearer the figures. 

3. Some formulas lack specific explanations for the meaning of letters, which should be checked and supplemented completely.

Thank you for your valuable comment. We modified the manuscript where needed.

4. The gas name symbol in Figure 4 should be modified to subscript.

Thank you for your comments. In the legend of excel it is not allowed to report the subscript.

5. The clarity of some cited images is relatively low.

We tried to improve some figures but some of them (published by other authors) are retrieved by published papers and the quality can be a bit low. However, the text provides full explanation in order to better understand what they want to show.

Reviewer 2 Report

Comments and Suggestions for Authors

1.    Comments to the Authors

1.1.        Analysis of merits

The paper, with reference number geosciences-2982828, presents an exhaustive review of the induced partial saturation (IPS) technique, emphasizing its innovative approach to mitigating the effects of soil liquefaction during earthquakes. The review is noteworthy for its in-depth analysis of mechanical principles and the detailed exploration of engineering applications. The Authors effectively highlight the eco-friendly and cost-effective attributes of IPS, addressing significant current challenges in geotechnical engineering. The structure of the review, including a broad survey of existing literature and synthesis of theoretical and practical insights, is commendably executed.

1.2.        Critical comments on the paper

While the review is methodologically comprehensive, certain areas require further elaboration for clarity and completeness:

1.       The review would benefit from a more detailed presentation of empirical data supporting IPS's efficacy. Including case studies or field applications where IPS has been implemented could provide practical insights and strengthen the review's comprehensiveness and credibility.

2.       The review outlines the advantages of IPS over traditional methods but lacks a detailed comparative analysis. A side-by-side comparison regarding cost, effectiveness, environmental impact, and practical deployment challenges would enrich the review's content and provide clearer guidance to practitioners and researchers.

3.       The long-term stability of gas bubbles within soil matrices and potential environmental impacts (e.g., effects on groundwater quality) are insufficiently discussed. Expanding on these topics would ensure the review comprehensively addresses all significant aspects of IPS's application.

1.3.        Overall evaluation

 

This review paper provides a significant contribution to the field of earthquake engineering by synthesizing a wide range of research findings on an innovative liquefaction mitigation technique. The potential of IPS to offer eco-friendly and economically viable solutions is well-articulated. Addressing the detailed points mentioned above, particularly concerning empirical evidence and comprehensive comparative analyses, will ensure that the review serves as a valuable and robust resource for both researchers and practitioners in geotechnical engineering. These revisions will greatly enhance the paper's influence and utility within the academic and professional communities.

Author Response

We appreciate the work of all reviewers, necessary to improve the manuscript. We are grateful to them. In the following we reported our replies and the modified version of the manuscript.

1. Comments to the Authors

1.1.        Analysis of merits

The paper, with reference number geosciences-2982828, presents an exhaustive review of the induced partial saturation (IPS) technique, emphasizing its innovative approach to mitigating the effects of soil liquefaction during earthquakes. The review is noteworthy for its in-depth analysis of mechanical principles and the detailed exploration of engineering applications. The Authors effectively highlight the eco-friendly and cost-effective attributes of IPS, addressing significant current challenges in geotechnical engineering. The structure of the review, including a broad survey of existing literature and synthesis of theoretical and practical insights, is commendably executed.

1.2.        Critical comments on the paper

While the review is methodologically comprehensive, certain areas require further elaboration for clarity and completeness:

1. The review would benefit from a more detailed presentation of empirical data supporting IPS's efficacy. Including case studies or field applications where IPS has been implemented could provide practical insights and strengthen the review's comprehensiveness and credibility.

Thank you very much for your comment. In Figure 14 we reported, as an example, liquefaction resistance curves of saturated and partially saturated sands. It can be noted that liquefaction resistance of partially saturated sands is higher than that of saturated ones. Moreover, in the text we reported in line 426 other references to show the effectiveness of IPS at small scale. Additionally, consider that data in Figure 19 show the increase of liquefaction resistance of partially saturated sands compared to that of saturated ones. On the other hand, section 6.2 is devoted to the effectiveness of IPS at large scale. As known, little data is available in this case. Even though some authors studied IPS at real scale (Okamura et al., 2011 and more recently Moug et al., 2022), they didn’t check the effectiveness of IPS as mitigation technique against liquefaction. The effectiveness is studied by Flora et al., (2021), who used a seismic shaker to simulate the earthquake. We discussed in section 6.2. Other data are not yet available in literature.

2. The review outlines the advantages of IPS over traditional methods but lacks a detailed comparative analysis. A side-by-side comparison regarding cost, effectiveness, environmental impact, and practical deployment challenges would enrich the review's content and provide clearer guidance to practitioners and researchers.

Thank you for your comment. In section 1 we reported brief considerations about the traditional mitigation techniques against liquefaction. Since the review is long, as reported also by reviewer 3, we didn’t report any additional comment.

3. The long-term stability of gas bubbles within soil matrices and potential environmental impacts (e.g., effects on groundwater quality) are insufficiently discussed. Expanding on these topics would ensure the review comprehensively addresses all significant aspects of IPS's application.

Thank you for your valuable suggestion. The longevity of gas/air bubbles into soil is one of the most important topics of IPS. We agree with you that this part should be discussed more. Therefore we added in lines 705 – 714 further considerations and experimental results proposed by Zeybek & Madabhushi (2017).

1.3.        Overall evaluation

 This review paper provides a significant contribution to the field of earthquake engineering by synthesizing a wide range of research findings on an innovative liquefaction mitigation technique. The potential of IPS to offer eco-friendly and economically viable solutions is well-articulated. Addressing the detailed points mentioned above, particularly concerning empirical evidence and comprehensive comparative analyses, will ensure that the review serves as a valuable and robust resource for both researchers and practitioners in geotechnical engineering. These revisions will greatly enhance the paper's influence and utility within the academic and professional communities.

Reviewer 3 Report

Comments and Suggestions for Authors

Please reduce drastically the number of pages of the paper.

Author Response

We appreciate the work of all reviewers, necessary to improve the manuscript. We are grateful to them. In the following we reported our replies and the modified version of the manuscript.

Please reduce drastically the number of pages of the paper.

Reply:Thank you for your comment. Since there isn’t a number of page restrictions in Geosciences, we decided to maintain the original length. It is difficult to reduce the number of pages because the review deals with a new liquefaction mitigation technique and report several aspects from mechanisms at small scale until applications at large scale. We do believe that this paper can be useful to researchers and practitioners to better understand the mechanisms and the practical aspects linked to real applications.

Reviewer 4 Report

Comments and Suggestions for Authors

Title

Shaft Induced Partial Saturation: from mechanical principles to

engineering design of an innovative and eco-friendly countermeasure

against earthquake-induced soil liquefaction

Authors:

Lucia Mele, Stefania Lirer and Alessandro Flora

I am grateful for the opportunity to read this manuscript. The following

major changes should be made to this study during reading to improve its

quality:

Comments and Suggestions for Authors

Generally, the manuscript shows new contributions. Some additional references should

be included, some typos should be corrected, reorder the sections, and include a

separate discussion section.

The review has been carried out to be constructive, to make the article viable. The most

important task is to reorganize the content in accordance with a research article. Below

are the details.

1. What is the main question addressed by the research?

In this paper, the soil liquefaction induced by an earthquake is analyzed as a

catastrophic phenomenon. Among the effects can be damage to the foundations of

existing buildings and other structures. Traditional mitigation techniques against

liquefaction present critical aspects, such as the high cost of construction, among

others. Various aspects have been reviewed. The paper analyzes the effects of air/gas

bubbles on the cyclic behavior of sandy soils, the use of useful design graphs and

the effect of IPS under shallow foundations.

2. What parts do you consider original or relevant for the field? What specific gap in

the field does the paper address?

The authors use data from other research. The comparative analysis and the

demonstration that the use of IPS as a countermeasure against liquefaction is

effective, economical and ecological is original.

3. What does it add to the subject area compared with other published material?

Among other contributions, some illustrated applications are useful for technicians

and designers of earth dams and tunnels in soil.

 

2/2

4. What specific improvements should the authors consider regarding the

methodology? What further controls should be considered?

A section with the applied methodology in a synthesised form, i.e. with a flow chart,

is desirable. Otherwise, the steps followed blur into a set of perfectly valid but

mixed comparisons. As a script for a technical report it could be valid, but for a

research work it is necessary to detail the methodology.

5. Please describe how the conclusions are or are not consistent with the evidence and

arguments presented. Please also indicate if all main questions posed were

addressed and by which specific experiments.

Some of the sections are more specific to material and methods: 2 and 3. Sections

4 to 7 must be reorganized into results and discussion, either in independent sections

or in a single section. And the conclusions in an independent final section will

clarify the entire research process.

6. Are the references appropriate?

Yes, but in the introduction there are only 5 references. It does not constitute a

review of the state of the art. Furthermore, they have forgotten two important topics

in the context of the research that they must mention and reference with at least 1

reference each in the introduction:

a) Terzaghi's principle to estimate settlement of a building due to tunnel

construction.

The deformations generated by Terzaghi's Principle in a porous medium have

been solved in the context of tunnel construction in soft rock and granular

ground (i.e. https://doi.org/10.3390/buildings13051343)

b) Comparative analysis and evaluation of seismic response in structures:

perspectives from non-linear dynamic analysis to pushover analysis.

The basic analysis methods for earthquake and its effects on structures have

already been studied (i.e. https://doi.org/10.3390/app14062504)

7. Please include any additional comments on the tables and figures and quality of the

data.

The resolution of figures 6, 7, 9, 12, 21 and 22 must be improved. Some typos should

be corrected, i.e. in figure 22(b) the reference to figure 5 of the original base article

used should be removed..

I suggest writing the manuscript a major revisions, then publishing it.

I appreciate you.

Author Response

We appreciate the work of all reviewers, necessary to improve the manuscript. We are grateful to them. In the following we reported our replies and the modified version of the manuscript.

I am grateful for the opportunity to read this manuscript. The following major changes should be made to this study during reading to improve its quality:

Comments and Suggestions for Authors

Generally, the manuscript shows new contributions. Some additional references should be included, some typos should be corrected, reorder the sections, and include a separate discussion section.

The review has been carried out to be constructive, to make the article viable. The most important task is to reorganize the content in accordance with a research article. Below are the details.

1. What is the main question addressed by the research? In this paper, the soil liquefaction induced by an earthquake is analyzed as a catastrophic phenomenon. Among the effects can be damage to the foundations of existing buildings and other structures. Traditional mitigation techniques against liquefaction present critical aspects, such as the high cost of construction, among others. Various aspects have been reviewed. The paper analyzes the effects of air/gas bubbles on the cyclic behavior of sandy soils, the use of useful design graphs and the effect of IPS under shallow foundations.

Thank you for your kind comment.

2. What parts do you consider original or relevant for the field? What specific gap in the field does the paper address? The authors use data from other research. The comparative analysis and the demonstration that the use of IPS as a countermeasure against liquefaction is effective, economical and ecological is original.

Thank you for your kind comment. We do believe that this review can be useful for researchers and practitioners. It reports the main findings on this topic from mechanisms to possible applications.

3. What does it add to the subject area compared with other published material? Among other contributions, some illustrated applications are useful for technicians and designers of earth dams and tunnels in soil.

Thank you, we do believe that information reported in the paper can be useful to design this technique in situ.

4. What specific improvements should the authors consider regarding the methodology? What further controls should be considered? A section with the applied methodology in a synthesised form, i.e. with a flow chart, is desirable. Otherwise, the steps followed blur into a set of perfectly valid but mixed comparisons. As a script for a technical report it could be valid, but for a research work it is necessary to detail the methodology.

Thank you for your comment. Since it is a review, we didn’t report a design chart due to the fact that a methodology is not presented.  

4. Please describe how the conclusions are or are not consistent with the evidence and arguments presented. Please also indicate if all main questions posed were addressed and by which specific experiments. Some of the sections are more specific to material and methods: 2 and 3. Sections 4 to 7 must be reorganized into results and discussion, either in independent sections or in a single section. And the conclusions in an independent final section will clarify the entire research process.

Thank you for your comment. We believe that the review is well organized. In section 4 laboratory tests are presented; in Section 5 we discussed the parameters ruling the liquefaction resistance of partially saturated soils starting from experimental observations; in section 6 we extended the considerations at real scale. Additionally we proposed a design method for fix the degree of saturation to apply in situ to have a fixed increase of liquefaction resistance. In the last section (7) we dealt the effect of IPS on shallow foundations. Finally, we reported section 8 with the main conclusions and discussion.

6. Are the references appropriate? Yes, but in the introduction there are only 5 references. It does not constitute a review of the state of the art. Furthermore, they have forgotten two important topics in the context of the research that they must mention and reference with at least 1 reference each in the introduction:
7. a) Terzaghi's principle to estimate settlement of a building due to tunnel construction. The deformations generated by Terzaghi's Principle in a porous medium have been solved in the context of tunnel construction in soft rock and granular ground (i.e. https://doi.org/10.3390/buildings13051343)
8. b) Comparative analysis and evaluation of seismic response in structures: perspectives from non-linear dynamic analysis to pushover analysis. The basic analysis methods for earthquake and its effects on structures have already been studied (i.e. https://doi.org/10.3390/app14062504)

Thank you for your comment. We would like to say that in introduction we only reported 5 references because it deals with a comparison with the traditional mitigation techniques. Of course, the whole paper presents the state of the art of IPS. Therefore, the total number of references should be considered.

Regarding the papers you mentioned, we added them in the text.

7. Please include any additional comments on the tables and figures and quality of the data. The resolution of figures 6, 7, 9, 12, 21 and 22 must be improved. Some typos should be corrected, i.e. in figure 22(b) the reference to figure 5 of the original base article used should be removed.

 

Thank you for your comment. As we replied to Reviewer 1, we tried to improve some figures but some of them (published by other authors) are retrieved by published papers and the quality can be a bit low. However, the text provides full explanation in order to better understand what they want to show.

We would like to say that Figure 22(b) has been modified removing the reference to Fig 5 from the original paper. Thank you.  

 

I suggest writing the manuscript a major revisions, then publishing it.

I appreciate you.

 

 

Round 2

Reviewer 3 Report

Comments and Suggestions for Authors

The authors could divide the paper into 2 papers, part1 and part2. 

Reviewer 4 Report

Comments and Suggestions for Authors

Has made all the modifications requested by the reviewer.