Optimization of the Granular Mixture of Natural Rammed Earth Using Compressible Packing Model

Round 1

Reviewer 1 Report

I read the whole manuscript. It is interesting but before accept the manuscript the minor revision is needed. 

1. Please improve the english language of the manuscript.

2. Improved the figure quality.

3. In the conclusion section please added the main objective of the research work.

4. Please added the scope of work in the future. 

Author Response

Point 1: Please improve the english language of the manuscript

 

Response 1: a language revision was done to improve the manuscript

 

Point 2: Improved the figure quality.

 

Response 2: Done (See article)

 

Point 3:  In the conclusion section please added the main objective of the research work

Response 3:

Rammed earth is an eco-friendly material to reconsider as a sustainable solution and an alternative to conventional materials. Constructors, engineers, and architects need a scientific result to make RE design and construction easy and justified. The objective of this paper was to apply the CPM on RE material to define a precise and optimal granular mixture which provides higher compactness and notably better mechanical performance. The relevance of this theoretical model is evaluated through an experimental protocol for two different recipes: The original soil (E2) and the optimized granular mixture (E3). Results show that any extracted grounded soil can be corrected by adjusting the dosages of its granular classes in order to achieve optimum compactness.

 

Point 4:  Please added the scope of work in the future.

In the future, RE material compactness and mechanical strength could be predicted by a simple granular correction with any raw granular material. Using stabilizing agents especially lime will allow to improve these characteristics. The improvement of RE mechanical performance can also be achieved by reconsidering the compaction process and energy. Further works and extended application of this model in real projects should enhance this methodology and set up a specific RE database.

Reviewer 2 Report

1. As recommended, a need of water test is conducted. It consists of mixing 715g of fines

(Pp) progressively by adding controlled quantity of water until the soil is no more humid (Error!  Reference source not found.) Reference source not found.

2. To measure compactness of sand and gravel, a precise quantity (7,5Kg of gravel and 269

3Kg of sand) is shaken in a sieve shaker for 1 minute under a pressure of 10kPa (Error!  270

Reference source not found.) Reference source not found.

3. It is suggested to center the picture and formula.

4. The third picture in Figure 4 is not aligned horizontally and Figure 6 is not aligned vertically

5. Put the header and body of Table 6 on one page.

6. There is a punctuation problem in the conclusion, and it is suggested to use a period at the end of each line in the striped summary.

7. The arrow in Figure 12 needs to be corrected, and part of the text in the figure box is not fully displayed.

Author Response

 

Point 1: As recommended, a need of water test is conducted. It consists of mixing 715g of fines

(Pp) progressively by adding controlled quantity of water until the soil is no more humid (Error!  Reference source not found.) Reference source not found.

 

Response 1:

 Sedran, T., & de Larrard, F. (1994). RENÉ-LCPC: un logiciel pour optimiser la granularité des matériaux de génie civil. Bulletin de liaison des Laboratoires des Ponts et Chaussées, (194).

 

Point 2: To measure compactness of sand and gravel, a precise quantity (7,5Kg of gravel and 269

3Kg of sand) is shaken in a sieve shaker for 1 minute under a pressure of 10kPa (Error!  270

Reference source not found.) Reference source not found

 

Response 2:

Sedran, T., & de Larrard, F. (1994). RENÉ-LCPC: un logiciel pour optimiser la granularité des matériaux de génie civil. Bulletin de liaison des Laboratoires des Ponts et Chaussées, (194).

 

Point 3: It is suggested to center the picture and formula.

Response 3 : Done (See the revised manuscript)

 

Point 4: The third picture in Figure 4 is not aligned horizontally and Figure 6 is not aligned vertically

Point 5: Put the header and body of Table 6 on one page.

Response 4-5: Done (See the revised manuscript)

 

Point 6: There is a punctuation problem in the conclusion, and it is suggested to use a period at the end of each line in the striped summary.

Point 7: The arrow in Figure 12 needs to be corrected, and part of the text in the figure box is not fully displayed

Response 4-5: Done (See the revised manuscript)

 

 

Reviewer 3 Report

Currently, there are no relevant studies that propose a scientific approach to define clay, silt, sand and gravel dosages to optimize the compactness of the RE material. There are few standards for earth construction and all research is necessary.

Comments for author File: Comments.pdf

Author Response

Point 1: CRA-Terre is cited (Reference [10]) Page 2

Some technical documents, as CRA-Terre, precise also generic criteria that must be considered, such as, a red color of the soil, having a relatively low moisture, and being non-organic [10].

 

 

Point 2: Where the soils E1 and E2 are extracted from ?

 

Response 2: The soil E1 is extracted from the south of Morocco, in Tahnaout’s region, Marrakech. It is provided by Argilex bioconstruction, one of the most active earth construction companies in Morocco.

The soil E2 is obtained by sieving the soil E1 with a 10mm sieve to eliminate larger particles.

 

Point 2: Table 6: Why showing E1 and E2 results while testing E2 and E3

 

In the first paragraph, E3 is not defined yet using the CPM because the value of the compaction index is not determined yet. E1 and E2 samples were tested to obtain the experimental compactness and deduce via the CPM the compaction index (Equation 7).

Once K is defined, theorical simulations are realized to find the optimal mixture (E3) which had a compactness around 0,782.

Mechanical tests were realized on five differents soils with differents dosages but the article presents the original soil E2 and the optimal one E3 to show the relevance of the model.

The soil E1 was used to define experimental compactness and experimental compaction index but was eliminated in the mechanical tests because it contains so much gravel and it is no suitable for RE constructions according to the main standards

All the remarks on the manuscript were taken into account and corrected in the revised manuscript.

Round 2

Reviewer 2 Report

accept