Experimental Study of Influence of Freeze–Thaw Cycles on the Dynamic Properties of Weathered Sand-Amended Expansive Soils

Round 1

Reviewer 1 Report

The authors present an experimental study of the influence of freeze-thaw cycles on the dynamic properties of weathered sand-amended expansive soils in China to subgrade/pavement applications. The article is well-written and well-structured but needs revisions to improve it.

-Abstract. Please specify the Country (Xinjiang?)

-abstract. Please specify numerically which were the most promising results of the study.

-Authors need to improve the background. For example, no 2022-2023 references were added to the results' introduction or discussions. Some techniques have recently gained attention to stabilize granular soils like MCIP and others like one-part, two-part, or AA Alkali Activation-Geopolymers (for fine-grained soils). Please, describe the study's motivation for the abovementioned techniques.

-be careful with units. g/cm3 or KN/m3. Which do you think should be better? Be careful with the exponent 3.

-The (true) triaxial team needs more detail. For example, the sensitivity of stress and strain readings.

-table 1 and table 2. Describe (ie, define) the symbols in the text.

-in the phrase: The soil sample was compacted into 5 layers using the layered compaction method. Was the method static or dynamic.?

-Apparently, I have not understood the test's outline very well. The authors say they used true triaxial equipment. Usually, the samples to true triaxial are cubic, but then they say they used 5x10 cm cylindrical specimens. Please clarify.

-test conditions. Was any standard followed for dynamic tests? Are authors considering dynamic or cyclic tests?. Why were load stages increased?

-Table 4. Two decimals are ok.

-why only one damage model was used?

 

-results need to bring more numerical results.

Author Response

Please find the attachment, thank you.

Author Response File: Author Response.pdf

Reviewer 2 Report

The authors have studied the Influence of Freeze-thaw Cycles on the Dynamic Properties of Weathered Sand-amended Expansive Soils in China. The paper is well-written, experimentally sound, and presents results in a straightforward and accurate manner. However, I do have the following reservations:

1. There is a paucity of information on the study area and the location where soil samples were taken. I'd suggest authors go into more detail about this under the heading "Study area."

2. More effective discussion of the results is required.

 

3. In order to increase the study's effectiveness, the authors could cite more literature.

 

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 3 Report

It is mentioned that a large number of expansive soils are distributed in various places in China, such as Xinjiang (NW region) and Harbin (NE China region). Considering the importance of the geotechnical aspects mentioned and the relationships/damage with engineering works in transport infrastructure (roads), authors are recommended to prepare a Figure with the geographic location of these regions belonging to the seasonal frozen region, if possible, some detail of the current road network. It will certainly allow the reader a better understanding of the context presented in the manuscript.

The theme of the manuscript is well reasoned and contextualized. From a geotechnical point of view, what is the concept and meaning of altered sands and relative contents?

Taking into account the experimental focus of the study, it is suggested to expand and better present the details of Figure 1, to relate the instrumental apparatus described in item 2.1

Item 2.2 Authors are suggested to include field photos of the type of soil studied and the material being sampled

As for the test scheme (2.3) it is very well described, but a schematic figure covering the entire experimental protocol would be welcome to the reader.

Tests and analyzes (freeze-thaw cycle effects and impact of wet sand) properly discussed and quite consistent in terms of the established parametric approach. To make reading more adequate, Figs 5, 6, 7 and 8 could have the graphics more enlarged, as in the examples of Figs 10 and 11. In terms of the impact of weathered sand (Fig 8), why is the backbone curve of sand content =30% above the initial position? How can this be explained? Check text and symbology of Eq9

The analysis of the damage degree of the soil studied under the action of the geotechnical parameters (Hardin-Drnevich correction model) proves to be interesting and well-deep, and can be treated as a reference in other studies of the same focus and also for practical engineering

Quality of English Language is good.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

The manuscript can be accepted