A GIS-Based Kinematic Analysis for Jointed Rock Slope Stability: An Application to Himalayan Slopes

Round 1

Reviewer 1 Report

Excellent publication by the authors. I have no significant comments to make, just these minor ones below:

1) 1. Introduction

It is recommended to add the article's main (or general) aim, due to paragraph 1.1. (contributions) may confuse the reader about the main focus of the research.

2) 1.2. State-of-the-art

Figure 1 does not clarify where Xp, Xw and Xt are.

2) Introduction: 1.3. Kinematic susceptibility

This section mentions F1, F2, F3 and F4, but only F1-F2-F3 is related in equation 11. It would be necessary to add the relation with F4.

3) Results: line 505

Review the reference error.

4) Discussion

It is recommended to add the time period when the landslide inventory was carried out. This is, so that future readers know the inventory limit.

Author Response

Authors’ Response to Reviewer 1:

Dear Reviewer,

We would like to thank you very much for your time and constructive suggestions. We have addressed your comments and carefully proofread the manuscript. Please see our response below where the changes are also highlighted in the manuscript.

Best regards,

Authors

Excellent publication by the authors. I have no significant comments to make, just these minor ones below:

1) 1. Introduction

It is recommended to add the article's main (or general) aim, due to paragraph 1.1. (contributions) may confuse the reader about the main focus of the research.

Response: The authors are thankful for the suggestion. A general aim has been added to the introduction for better clarity to the reader.

“The main aim of this research article is to evaluate the efficiency of rock slope kinematic analysis in predicting shallow landslides in the Himalayan mountains on a regional scale with the help of a modified GIS-based technique.”

2) 1.2. State-of-the-art

Figure 1 does not clarify where Xp, Xw and Xt are.

Response: The X symbol stands for α, β or γ (angular relationship determinant). The same has been described in the manuscript.

3) Introduction: 1.3. Kinematic susceptibility

This section mentions F1, F2, F3 and F4, but only F1-F2-F3 is related in equation 11. It would be necessary to add the relation with F4.

Response: Thank you for pointing out the mistake. Actually, there was a typographic mistake in equation (10). Equations (9) and (10) are both F3 (equation (9) is for planar and wedge failure while equation (10) is for topple failure). Hope it is clear to understand now. And, F4 as you may know is related to damage characteristic of the slope and essential for Slope mass rating calculation. Therefore, we have not considered for the kinematic analysis. We also added

“There are other adjustment factors as described in Table 1 in [31]. For example,  varies from  to  depending on the excavation method of the slope: poor blasting (), normal blasting or mechanical excavation (), smooth blasting (), pre-splitting (), and natural slope (). However, since  is related to damage characteristic of the slope and essential for slope mass rating calculation, we did not consider it for kinematic analysis.”

 

4) Results: line 505

Review the reference error.

Response: Thank you for pointing out the error. We have corrected it.

5) Discussion

It is recommended to add the time period when the landslide inventory was carried out. This is, so that future readers know the inventory limit.

Response: Thank you for the valuable comment. We have added the relevant information.

“For validation purposes, an inventory of landslides in the area was prepared. Some of the landslides in the area were detected during the field investigations, but many of them were identified on Google Earth images by navigating through the temporal satellite images in the study area from 2008 to 2019. The inventory layer is shown in Figure 11.”

 

 

Author Response File: Author Response.pdf

Reviewer 2 Report

The manuscript entitled “A GIS-Based Kinematic Analysis for Jointed Rock Slope Stability: An Application to Himalayan Slopes”, by J. Kundu, K. Sarkar, E. Ghaderpour, G.S. Mugnozza, P. Mazzanti, presents an interesting work.

In general, the manuscript should be acceptable for publication but some serious problems must be repaired prior to publication. It needs some significant improvement. Some suggestions are as follows:

 

1. An extensive discussion would improve your paper.
2. The abstract should state briefly the purpose of the research, the principal results and major conclusions. An abstract is often presented separately from the article, so it must be able to stand alone.
3. The English language usage should be checked by a fluent English speaker. It is suggested to the authors to take the assistance of someone with English as mother tongue.
4. It would be useful to be described the aim of this paper.
5. You could enrich the scientific literature.
6. Please justify convincingly why this manuscript (method, thematology etc) connected with Land’s content and scope. Perhaps the using of proper literature from this journal would be helpful. You could see and use the following publications: “Land Use Planning for Natural Hazards”, Land, 8 (9): 128 & “Physical and anthropogenic factors related to landslide activity in the Northern Peloponnese, Greece”. Land, 7 (3): 85.
7. The authors could see and use the following publication: “Hazard zonation mapping of earthquake-induced secondary effects using spatial multi-criteria analysis. Nat Hazards, 109 (1): 637 – 669
8. Please use coordinates in all maps.
9. When you are using coordinates, please do not use “North Arrow”. My opinion is that it is a mistake in cartography.
10. Correct references in the text and the reference list according to the journal’s format. Please format the references’ list by using the correct journal abbreviations. See the following link: https://images.webofknowledge.com/images/help/WOS/A_abrvjt.html      

 

Author Response

Authors’ Response to Reviewer 2:

Dear Reviewer,

We would like to thank you very much for your time and constructive suggestions. We have addressed your comments and carefully proofread the manuscript. Please see our responses below where the changes are also highlighted in the manuscript. Hope the changes we made are satisfactory.

Best regards,

Authors

Comments and Suggestions for Authors

The manuscript entitled “A GIS-Based Kinematic Analysis for Jointed Rock Slope Stability: An Application to Himalayan Slopes”, by J. Kundu, K. Sarkar, E. Ghaderpour, G.S. Mugnozza, P. Mazzanti, presents an interesting work.

In general, the manuscript should be acceptable for publication but some serious problems must be repaired prior to publication. It needs some significant improvement. Some suggestions are as follows:

 

1. An extensive discussion would improve your paper.

Response:  We have expanded the discussion section and added a few recent relevant publications in relation to the work to improve the section. We added:

“Susceptibility and hazard assessment for landslides in mountainous regions is vital to manage the regional scale of landslide risk. The slopes which are always under the action of gravity may fail when they meet unfavourable morphology, lithology, structures, and various triggering factors. The relation of physical and anthropogenic factors to landslide activity is described by Skilodimou et al. [83]. Earthquake activity poses a significant danger to critically stable slopes, and the associated hazard to landslide should properly be assessed [84]. Ji et al. have developed a GIS-based tool for probabilistic assessment of the effect of an earthquake on mountain slopes, which could be implemented for hazard mapping of earthquake-induced landslides [85]. Anthropogenic activities carried out on mountain slopes should be properly defined with a suitable land-use plan [86]. The present article showed the effect of spatially distributed geo-structures on the failure susceptibility of rock slopes. The same has been again evaluated against the ground truth through statistical means. The geomorphic, lithologic causative factors as well as other environmental factors rainfall, and earthquakes have a significant impact on the landslide susceptibility of mountain slopes. However, this article is dedicated to kinematic susceptibility aiming at a clear picture of the effect of the geo-structure orientations on landslides in rock slopes.

As mentioned in Section 2.3, the entire algorithm of GISMR is based on a cell-by-cell calculation method. Analysing slope units to kinematic failure may also be useful, but it may confront the following difficulties. A slope unit may have different slope angles in different parts of the unit, and therefore, a uniform slope angle for the analysis of the whole area inside the unit may not be justified. In practice, the whole slope unit is not always susceptible to failure rather a part of it may fail due to unfavourability in that particular region. The joint orientations may vary within a slope unit which makes it difficult to analyse the slope accurately based on the slope unit. Therefore, though pixel-based analysis may discretize the slopes, it provides an overall view of the susceptibility of the region inside the slope unit. Moreover, the benefit of this pixel-based procedure is that one can differentiate the type of failure that is affecting each pixel of the region.”

 

2. The abstract should state briefly the purpose of the research, the principal results and major conclusions. An abstract is often presented separately from the article, so it must be able to stand alone.

Response: Thank you for your suggestion. The abstract has been modified according to your suggestion.

 

3. The English language usage should be checked by a fluent English speaker. It is suggested to the authors to take the assistance of someone with English as mother tongue.

Response: The manuscript was read by a native speaker and checked for error and possible improvements.

 

4. It would be useful to be described the aim of this paper.

Response: The aim of the paper has been added to the introduction part of the paper. Thanks for the comment. At the beginning of Section 1.1, we wrote:

“The main aim of this research article is to evaluate the efficiency of rock slope kinematic analysis in predicting shallow landslides in the Himalayan mountains on a regional scale with the help of a modified GIS-based technique.”

 

5. You could enrich the scientific literature.

Response: The introduction and discussion were improved with reference to recent relevant literature. The following recent articles were added and discussed in Introduction and Discussion sections:

• Ji, J.; Cui, H.; Zhang, T.; Song, J.; Gao, Y. A GIS-based tool for probabilistic physical modelling and prediction of landslides: GIS-FORM landslide susceptibility analysis in seismic areas. Landslides 2022, 19, 2213–2231. https://doi.org/10.1007/s10346-022-01885-9
• Ji, J.; Wang, C.-W.; Cui, H.-Z.; Li, X.-Yu.; Song, J.; Gao, Y. A simplified nonlinear coupled Newmark displacement model with degrading yield acceleration for seismic slope stability analysis. Int J Numer Anal Methods Geomech. 2021; 45, 1303–1322. https://doi.org/10.1002/nag.3202
• Skilodimou, H.D.; Bathrellos, G.D.; Koskeridou, E.; Soukis, K.; Rozos, D. Physical and Anthropogenic Factors Related to Landslide Activity in the Northern Peloponnese, Greece. Land 2018, 7, 85. https://doi.org/10.3390/land7030085
• Karpouza, M.; Chousianitis, K., Bathrellos, G.D.; Skilodimou, H.D.; Kaviris, G.; Antonarakou, A. Hazard zonation mapping of earthquake-induced secondary effects using spatial multi-criteria analysis. Nat Hazards 109, 637–669 (2021). https://doi.org/10.1007/s11069-021-04852-0
• Bathrellos, G.D.; Skilodimou, H.D. Land Use Planning for Natural Hazards. Land 2019, 8, 128. https://doi.org/10.3390/land8090128

6. Please justify convincingly why this manuscript (method, thematology etc) connected with Land’s content and scope. Perhaps the using of proper literature from this journal would be helpful. You could see and use the following publications: “Land Use Planning for Natural Hazards”, Land, 8 (9): 128 & “Physical and anthropogenic factors related to landslide activity in the Northern Peloponnese, Greece”. Land, 7 (3): 85.

Response: Thank you for your suggestion. The suggested relevant literatures have been reviewed in the manuscript. Please see the Discussion section.

 

7. The authors could see and use the following publication: “Hazard zonation mapping of earthquake-induced secondary effects using spatial multi-criteria analysis. Nat Hazards, 109 (1): 637 – 669

Response: The suggestion has been incorporated. Please see the discussion section. Thank you.

 

8. Please use coordinates in all maps.

Response: Coordinates have been added to all the maps wherever necessary.

 

9. When you are using coordinates, please do not use “North Arrow”. My opinion is that it is a mistake in cartography.

Response: The suggestion has been incorporated into the maps. In addition, we improve the quality/resolution of all the maps.

 

10. Correct references in the text and the reference list according to the journal’s format. Please format the references’ list by using the correct journal abbreviations. See the following link: https://images.webofknowledge.com/images/help/WOS/A_abrvjt.html      

Response:  Thank you for the suggestion, the references have been checked according to the indicated format and MDPI guideline.

Author Response File: Author Response.pdf

Reviewer 3 Report

This manuscript presents a GIS-Based kinematic analysis for jointed rock slope stability and applies it to Himalayan slopes. The topic is interesting and important in the hazard assessment of the mountainous region. This method is proved to be effective and convenient by developing the “GISMR” tool. However, there is some important issues to be considered for publication in the Land journal.

Specific comments:

1.     In Fig.2: Geological map of the study area. Please use the clearer version.

2.     Table 1 is too long. The authors are suggested to use the chart instead of the table.

3.     The results and analyses of full text and GISMR tool only consider the normal condition, namely, gravity. On the contrary, the other important influence factors are neglected, such as earthquakes and rainfall, etc. The authors are suggested to clarify the reasons about these factors are not taken into account.

4.     Line 338-339: The authors said that the entire algorithm of GISMR is based on a cell-by-cell calculation method using the information in grided text format. In the reviewer’s opinion, since the failure mode of rock slopes are considered, such as planar, wedge and topple, the failure mechanisms of rock slopes will become very complex and calculations based on cell-by-cell are worthing to ponder. Because from this point, a rock body is divided into many columns body in terms of analyzing the failure process. The slope unit is maybe more suitable. The authors are recommended to clarify.

5.     Section 2.3.5: “The angle of friction for different rocks was determined through the tilt test method at various locations in the area and a mean friction angle of 26° was consideration for the analysis.” The reasons for using the mean value of friction angle should be explained. I also would like to know if the authors have done some sensitivity analysis of parameters. The effect of using the mean value of the friction angle as an input parameter on the final result, the authors are suggested to clarify it.

6.     Line 570-572: “We have used the frequency ratio method to quantify the associations between kinematically susceptible pixels and actual landslides. Frequency ratio (FR) is a well-established method to check the sensitivity ….”. Why don’t apply the ROC value to judge the accuracy between prediction and reality? Because the receiver operating characteristic (ROC) analysis can compare the performance of the different simulation results. The authors are suggested to add the analysis of ROC.

7.     The literature review is not complete. There are some recent publications about hazard assessment based on GIS. The authors are suggested to further investigate those materials. For example, https://doi.org/10.1007/s10346-022-01885-9.

 In summary, this manuscript is recommended for major revisor.

Author Response

Authors’ Response to Reviewer 3:

Dear Reviewer,

We would like to thank you very much for your time and constructive suggestions. We have addressed your comments and carefully proofread the manuscript. Please see our responses below where the changes are also highlighted in the manuscript. Hope the changes we made are satisfactory.

Best regards,

Authors

Comments and Suggestions for Authors

This manuscript presents a GIS-Based kinematic analysis for jointed rock slope stability and applies it to Himalayan slopes. The topic is interesting and important in the hazard assessment of the mountainous region. This method is proved to be effective and convenient by developing the “GISMR” tool. However, there is some important issues to be considered for publication in the Land journal.

Specific comments:

1. In Fig.2: Geological map of the study area. Please use the clearer version.

Response: Thanks for the suggestions. We have added a high resolution image and improved the figure for a better readability.

2. Table 1 is too long. The authors are suggested to use the chart instead of the table.

Response: Thank you for your comment. Indeed, both Table 1 and 2 are long, and we decided to move them to Appendix (at the end of manuscript). Table 1 is mostly descriptive and subjective, so we think it is suitable to present the information in table format. We have reduced the text in this table to fit in one page. We also added a description for your suggested article at the last row of this table.

3. The results and analyses of full text and GISMR tool only consider the normal condition, namely, gravity. On the contrary, the other important influence factors are neglected, such as earthquakes and rainfall, etc. The authors are suggested to clarify the reasons about these factors are not taken into account.

Response: Authors thank the reviewer for pointing out a relevant discussion to be added to the manuscript. The authors have dedicated the article to evaluate the effect of the structure orientation on the landslide activity. The authors have conducted the effect of other geomorphic and environmental causative factors on the landslide susceptibility. However, the study would be extensive less focused for this article therefore, decided to communicate in another publication.  We have added a brief discussion on the matter in the discussion section.

4. Line 338-339: The authors said that the entire algorithm of GISMR is based on a cell-by-cell calculation method using the information in grided text format. In the reviewer’s opinion, since the failure mode of rock slopes are considered, such as planar, wedge and topple, the failure mechanisms of rock slopes will become very complex and calculations based on cell-by-cell are worthing to ponder. Because from this point, a rock body is divided into many columns body in terms of analyzing the failure process. The slope unit is maybe more suitable. The authors are recommended to clarify.

Response: The point mentioned by the reviewer is worth discussing. We agree that analyzing slope units to kinematic failure has its own advantages. But it is more likely to confront with following difficulties.

“A slope unit may have different slope angles in different parts of the unit and therefore, a uniform slope angle for the analysis of the whole area inside the unit may not be justified. Also, if we observe practical examples, the whole slope unit is not always susceptible to failure rather a part of it may fail due to unfavourability in that particular region.

The joint orientations may vary within a slope unit which makes it difficult to analyze the slope accurately on the basis of slope unit. Therefore, though pixel based analysis discretize the slopes, it provides an overall view of the susceptibility of the region inside the slope unit. Moreover, the benefit of this pixel based procedure is that we can differentiate the type of failure that is affecting each pixel of the region.”

We have added the texts above in the Discussion section, and we shall consider it more rigorously in our future research.

5. Section 2.3.5: “The angle of friction for different rocks was determined through the tilt test method at various locations in the area and a mean friction angle of 26° was consideration for the analysis.” The reasons for using the mean value of friction angle should be explained. I also would like to know if the authors have done some sensitivity analysis of parameters. The effect of using the mean value of the friction angle as an input parameter on the final result, the authors are suggested to clarify it.

Response: We added in Section 2.3.5, the following:

“Several friction angles were collected through tilt test method at different locations along the National Highway running through the mountainous region. There were also few locations far away from the highway for which friction angles were determined. We observed a significant variation in the friction angle even in same lithology (probably due to different roughness pattern) and with no distinct range between different lithology. Moreover, our dataset was not uniformly collected throughout the region due to inaccessibility in the high, uneven and treacherous mountains. Therefore, we considered the mean value of the friction angle.”

The authors have not performed sensitivity analysis of all the parameters in this study. However, we appreciate the suggestion and implement it in our future work.

6. Line 570-572: “We have used the frequency ratio method to quantify the associations between kinematically susceptible pixels and actual landslides. Frequency ratio (FR) is a well-established method to check the sensitivity ….”. Why don’t apply the ROC value to judge the accuracy between prediction and reality? Because the receiver operating characteristic (ROC) analysis can compare the performance of the different simulation results. The authors are suggested to add the analysis of ROC.

Response: We thank the reviewer for the suggestion. In the Discussion section, we also added a ROC curve for the analysis results.

7. The literature review is not complete. There are some recent publications about hazard assessment based on GIS. The authors are suggested to further investigate those materials. For example, https://doi.org/10.1007/s10346-022-01885-9.

Response: The authors sincerely thank the reviewer for the suggestion. The suggested article is added and discussed in Table 1 and in the Discussion section. Some other recent relevant publications for slope stability analysis have been added to the Introduction and Discussion.

 

In summary, this manuscript is recommended for major revisor.

Response: Thank you. We have also incorporated the comments from other two reviewers and carefully proofread the manuscript.

 

 

Author Response File: Author Response.pdf