A Case Study of a Large Unstable Mass Stabilization: “El Portalet” Pass at the Central Spanish Pyrenees

Round 1

Reviewer 1 Report

lineline 13 conducted rather than conducting

line15 omit works

line 30 affect rather than affection, on rather than to

line 38 to rather for  

line 40 and 41 occurred rather than was found

line 49 appeared rather than appear

line 62 omit the

line 63 different rather than differential

line 66 omit also

line 67 & 68 These data are

line 87 contains rather than conforms

line 89 active rather than activity

line 90, portions rather than sectors

line 116 add s to investigation

line 126 located rather than placed

line 142 year's time, omit once implemented

line 149 replace pipes of with pipes withl

line 158 omit first the,replace of with on

;ine277 replace in with at

There could be more corrections in last portion of paper

 

Author Response

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Reviewer 2 Report

The article presents the stabilization measures taken to stabilize a landslide in Spain, triggered by the construction of a parking. The paper is overall interesting; however the authors should address some issues. Furthermore, despite understandable, English needs some improvements. Therefore, according to this Reviewer, a revision would be necessary. All details are summed up in the following.

 

Required changes:

1. Some English editing is needed.
2. Introduction is too short and should be extended. In particular, only 8 rows (from line 29 to line 36) currently describe the problem dealt with in the present paper, whereas the remaining part is devoted to the considered landslide. However, since the Authors discuss a concept of performance based techniques, in which the stabilization measurements are aimed to reduce the landslide mobility rather than stop the whole landslide body and provide a very high factor of safety, a more detailed discussion should be provided about this point. In this context, several studies are available in the literature concerning this problems, such as for example drainage systems [1] and stabilizing piles [2]. For the sake of completeness, these suggested references are reported at the end of this report.
3. Figure 3 should better highlight the comparison between the slope profiles before and after the stabilization measure. A distance scale (for vertical and horizontal direction) should also be added.
4. The points described at lines 143-154 should be well identified in Figure 3.
5. Line 303: indicate how the seismic action was taken into account.
6. Table 1: are the cohesion and friction angle in this table referred to peak or residual condition?
7. Lines 306-307: to obtain this value of the factor of safety, were the parameters reported in table 1 employed? If yes, this should be indicated at these lines. Was it a reactivation or a first time failure?
8. Figure 9b, in comparison with figure 9a the water table is changed a lot due to the drainage system. How did the authors calculate the final position of water level?

 

SUGGESTED REFERENCES

[1] Wei, Zl., Wang, Df., Xu, Hd. et al. Clarifying the effectiveness of drainage tunnels in landslide controls based on high-frequency in-site monitoring. Bull Eng Geol Environ 79, 3289–3305 (2020).

[2] Troncone A., Pugliese L., Lamanna G., Conte E. (2021). Prediction of rainfall-induced landslide movements in the presence of stabilizing piles. Engineering Geology 288, 106143.

 

 

Author Response

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Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

The authors have properly addressed the issues previously raised. However, the answers and the new version of the manuscript contain a new piece of information which is not convincing. In particular, as a response to comment n. 6, the authors write that the shear strength parameters (table 1) refer to the residual condition. Afterwards, responding to comment n. 7, the authors write that the landslide was a first time failure (as also reported in the manuscript, where it is also clearly highlighted that the landslide was not a reactivation). Despite that, the authors employed the residual shear strength parameters to analyze a first time failure. However, the residual shear strength parameters should be used when dealing with a reactivation. On the contrary, for a first time failure, the parameters should correspond to the peak condition or, if the soil is characterized by a pronounced strain softening behavior, an operative value intermediate between peak and residual condition should be employed. In this latter case, a numerical analysis that accounts for the strain softening behavior would be more appropriate. Said that, I am not asking the authors to change their calculation, but I cannot understand why they used the residual strength parameters for a first time failure.

Author Response

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