Exploring the Effects of the Substitution of Freshly Mined Sands with Recycled Crushed Glass on the Properties of Concrete

Round 1

Reviewer 1 Report

This paper is a useful characterization of concrete with recycled crushed glass. However, before acceptance requires mayor changes, whose suggestions are described below:

1. Introduction (36). The amount of consumption of concrete (12 billion tonnes) is outdated (2010). There are more current references of 35 billion tonnes.

K.L. Scrivener, V.M. John, E.M. Gartner, Eco-Efficient Cements: Potential, Economically Viable Solutions for a Low-CO2, Cement-Based Materials Industry, United Nations Environment Program, 2016 (available on), www.unep.org

1. 2. Waste glass as resource for Construction Materials (124). Pozzolanic reactions occur with vitreous siliceous materials.
2. 3. Materials and methods. The densities of recycled crushed glass and freshly mined sand have not been indicated.
3. 3.3 Concrete mix design (204). Design guide published by Buckeridge Group of Companies is not indicated in references.
4. 4. Results and Discussion (Figure 5). AS Specification is not explained in the text.
5. 4.3.1. Density (Table 2). Which is the difference between columns 4 and 5?.
6. 4.3.1. Density (Figure 10). Density is kg/m3.
7. 4.3.1. Density (Table 2 and Figure 10). It is recommended not to duplicate data in tables and figures. It would be better to make a figure that includes all the data in the table and delete the table.
8. 4.3.2. Water Absorptivity (Table 3 and Figure 11). Data in the table is duplicated in the figure. The results are better understood in the figure.
9. 4.3.3 Compressive Strength. Peak strength with 15% glass substitution could be due to greater compactness of the mixture. Glass particles fill the gaps in the sand. It is recommended to draw the granulometric curves of the mixed aggregates with different substitutions and compare them with the ideal curves (Fuller, Bolomey).
10. 4.3.3 Compressive Strength (Table 4 and Figure 14). Data in the table is duplicated in the figure. The results are better understood in the figure.
11. 4.3.3 Compressive Strength (Figure 14). The property of the x-axis is missing (% CWG proportion in Concrete Mixture).
12. 4.3.4 Splitting Tensile Strength (Figure 13). The figure is wrongly numbered, it is 14. The property of the x-axis is missing (% CWG proportion in Concrete Mixture).
13. 4.3.5 Flexural Strength (Figure 15). The property of the x-axis is missing (% CWG proportion in Concrete Mixture).
14. 4.4 SEM Analysis and effects of glass substitution on mechanical properties (737). Formation is duplicated.
15. 5. Conclusions. Include the result of the analysis of the compactness of the different granulometric mixtures.

Author Response

We have responded to Reviewer 1 as appended. 

Author Response File: Author Response.docx

Reviewer 2 Report

Dear authors,

I really appreciate the choice of the topic of the article. I fully understand the focus on a clear hypothesis and a narrowly specified area of research.

A few notes:
I did not find information about the number of samples for each test. Is it possible to add?
If you have measured a sufficient number of samples, can you state the standard deviations?
For such "new" materials, the variance of values is very important.

I understand well that in this work you analyze the mechanical properties of new concrete mixtures, but do you not analyze other properties in any way? So what type of construction is suitable for this type of concrete, if you use exactly 15% of CWG?

Graphic recommendation:
Some pictures are in the frame, others are not - it should be uniform.
The abstract exceeds the maximum length of 200 words.
Some sheets have blank lines at the top and bottom. This is probably a problem when uploading a file to the system.

Concluding remarks:
Missing chapter recommendation from template: Author Contributions, Funding, Conflicts of Interest etc.

Regards

Author Response

Response to Reviewer 2 as appended.

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

The suggestions have been taken into account

Reviewer 2 Report

Dear authors,
Thank you so much for editing the article. The article is now suitable for publication.
Regards,