A Substitute for Portland Cement: Experiments on Ecofriendly Reinforcement of Large-Scale Calcareous Sand by Microbial-Induced Carbonate Precipitation Spraying Method

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Line 110. In Figure 1 there is no designation of sensors marked as a#, b#, c#, d#. Please add this;

Line 119. Figure 1. The Figure is missing position (a), which is responsible for the “sand column”;

Line 146. Figure 3. It is recommended to explain what the levels a#, b#, c#, d#, marked on the schematic diagram, mean?;

Lines 221, 223, 241. Please explain, what does Case 1 – Case 7 mean in Figures 5–7;

Line 357. Please, explain how you can track changes in concentration of CS in Figure 10.

Author Response

"Please see the attachment." 

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

1.    The title should be revised to provide a more precise and descriptive representation of the research, capturing the utilization of MICP 12 technology for calcareous sand reinforcement as a substitute for Portland cement in response to the greenhouse effect and sustainable development goals.

2.    The abstract lacks a concise problem statement, which should clearly articulate the need for investigating the effects of initial water level and concentration of cementing solution (CS) on the reinforcement process using MICP 12 technology.

3.    The methodology section should be expanded to elucidate the experimental setup and conditions in greater detail, including specific parameters such as temperature, pressure, and duration of the spraying method employed for MICP 12 treatment.

4.    While the results section effectively outlines the observed patterns in penetration resistance and equivalent calcium carbonate content, it would be advantageous to incorporate appropriate statistical analysis techniques to assess the statistical significance of the observed differences.

5.    The discussion section could be further developed to provide comprehensive interpretation of the results, linking them to previously published studies and addressing the practical implications of the findings for engineering applications and sustainable construction practices.

6.    A concise conclusion is needed to summarize the main findings of the study, highlight their significance in the context of calcareous sand reinforcement, and potentially suggest avenues for future research.

7.    The reference list should be carefully reviewed to ensure accuracy, consistency, and adherence to the specified citation style throughout the manuscript.

Author Response

"Please see the attachment." 

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

In the paper, authors used MICP 12 technology based on the spraying method as a substitute for Portland cement to reinforce 13 calcareous sand. The effects of different parameters on the reinforcement were analyzed.

 

 

Comment (1): On equation 1, what does mean #𝑢𝑟𝑒𝑎se#

Comment (2): The mechanical properties of new materials is not studied

Comment (3): please define the acronyms before using it, for example: MICP

Comment (4): The literature review about using other material that can substitute Portland cement is very limited. Please enrich the introduction by discussing other references.

Comment (5): Please compare the developed method with existing ones.

 

In my opinion this paper needs major revision and the important missing parts are the bibliography, the novelty and the importance of this research and then the mechanical characteristics of the new method.

Author Response

"Please see the attachment." 

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

Manuscript can be accepted in present form

Reviewer 2 Report

Comments and Suggestions for Authors

accept

Reviewer 3 Report

Comments and Suggestions for Authors

The quality of the paper is improved and it can be accepted