Experimental and Estimated Evaluation of Drying Shrinkage of Concrete Made with Fine Recycled Aggregates
Round 1
Reviewer 1 Report
1. A brief summary
The manuscript "Experimental and estimated evaluation of drying shrinkage of concrete made with fine recycled aggregates" reports on the influence of different characteristics of fine recycled concrete aggregates on the drying shrinkage of concrete. The evaluation of the suitability for predicting drying shrinkage of concrete with FRCA contributes to the knowledge of the behavior of these aggregates in concrete mixtures and their use at the industrial level. In summary, this manuscript is suitable for the journal, but there are important observations that need to be addressed before the manuscript can be accepted.
2.Comments and suggestions
2.1. General concept comments
In the introduction, the relevance and innovation of the work carried out to achieve concrete sustainability are not clearly presented, even though the work is novel. In the same way, it is important to improve the timeliness of the referenced work. Also, it is indicated that during the last years, the use of FRCA has had a greater use in structural concretes, and papers that do not deal with structural concretes are referenced.
It is necessary to reformulate the section "Materials and Methods", detailing, as its name indicates, the materials used for the investigation and separately the different methods used. Furthermore, there is no mention of the methodology carried out for the indicated results of compressive strength, static modulus of elasticity, and drying shrinkage, so the results of the manuscript can be reproducible.
There are problems concerning for the the mention of different issues that prevent a correct compression of the manuscript such as:
- It is indicated that the aggregates are obtained from four sources of concretes, however, it is not indicated at the age of curing that these concretes were owned when they were processed. This is relevant due to the hydration progress of the cementitious paste, since the number of pores may vary with time.
What does it mean that the actual water absorption by the aggregates cannot be reliably quantified?
2.2. Minor comments
On line 368, equations 3 to 6 are given, which are not presented in the manuscript.
On line 163, "add 3" is indicated.
Improve the introduction of the equations in the manuscript, specifically what is indicated between lines 357 and 384.
In line 368, equations 3 to 6 are indicated, which is not presented in the manuscript.
Author Response
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Author Response File: 
Author Response.docx
Reviewer 2 Report
The authors have studied the drying shrinkage of concrete made of fine recycled aggregates. It is an interesting topic, and enormous studies have been conducted on the use of fine or coarse recycled aggregates in concrete products. The authors should highlight the research gap and the novelty of this study. Moreover the abstract needs to be revised to include a summary of the results.
Overall, the manuscript meets the technical requirements of a research article, and the quality of the presentation is good. However, the manuscript requires some language polishing and minor formatting and reference correction. For instance, in line 45 the citation format should be Author[year] not numbering. There is also a highlighted reference in line 163.
Author Response
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Author Response File: Author Response.docx
Reviewer 3 Report
This work is devoted to the systematization of the study of the properties of concrete. I find this work interesting and relevant. Below I provide comments.
. Line 86 - I recommend specifying the units of measurement for density and all other characteristics
2. Section 2 – I recommend restructuring and reorganizing the Materials and methods section. At the moment, the section does not fully explain the methodology of the experiment
3. Section 3.1 - It is unclear how and where these indicators were established. A methodological part or links are required.
4. Line 136 – Yellow marker need correction
5. Figure 1, 4 are unreadable and require errors.
6. Line 357 – I recommend to restructure the formula. It is unclear and hard for understanding.
Author Response
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Author Response File: Author Response.docx
Reviewer 4 Report
Dear Authors,
This article very important for the sustainable development of recycled concrete study, there are some comments on possible improvements below:
1. Detailed explanation on novelty of this research can be added by the end of Introduction section.
2. Figure 3 must be explained, because there are established unreliable correlation in case of “free water” and the same to Figure 7 (a).
3. All conclusions can be added with some recommendations for recycled concrete researchers and end users.
4. References are not necessary in case of repeating of well-known practice from not up to date articles:
8. Hansen, T. C. Recycled aggregate and recycled aggregate concrete. Second state of-the-art. Report developments. Materials and Structures 1986, 19(3), 1845-1985
9. Gottfredsen F.R.; Thogerson, F. Recycling of concrete in aggressive environment, demolition and reuse of concrete and 485 masonry. In Demolition and reuse of concrete and masonry, Proceedings of the Conference Third International RILEM 486 Symposium, Odense, October 1993, Lauritzen, E.K. Eds. RILEM 1994, 309-317.
50. Fava, A. Conocimientos y Medios Disponibles para Aumentar la Productividad en el Campo de la Tecnología del Hormi- 581 gón. Anales LEMIT 1968, 129(2), 1-37. 582
51. Nmai, C.K.; Tomita, R.; Hondo, F.; Buffenbarger, J. Shrinkage-Reducing Admixtures. Concrete International 1998, 20, 31-37. 583 52. Newman, J.B. Properties of structural lightweight aggregate concrete. Taylor & Francis, New York, USA, 1993.
Finally Authors can compare some results with other researchers studies: e.g.”Experimental research on quality parameters of recycled concrete. Materials. 2022” and/or related articles.
Sincerely, Reviewer.
Author Response
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