Analysis on Mechanical Properties of Recycled Aggregate Concrete Members after Exposure to High Temperatures
Round 1
Reviewer 1 Report
Please impove and address the following comments.
1) p3, L86, include water absorption rate of natural coarse aggregate (NCA)what is allowed as the limit of water absorption rate for RCA in China? Please describe that in the text. If the density of NCA is not same to that of RCA, the mixture proportion (Table 1) should be revised.
2) p4, L90, explain "I10 of Q235" clearly like section size and yielding strength etc.
3) Which standard is used for temperature increasing ?
4) What is the meaning of Fig 7(f) and (g)? reconsider the figures. And analyze more detailly test results and compare with existing test results.
5) present how to heat and load the specimens in text clearly. After heating then loading the specimens?
Author Response
Point 1: p3, L86, include water absorption rate of natural coarse aggregate (NCA)what is allowed as the limit of water absorption rate for RCA in China? Please describe that in the text. If the density of NCA is not same to that of RCA, the mixture proportion (Table 1) should be revised.
Response 1: At present, there is no relevant regulation on the limit of water absorption rate for RCA in China. The mixture ratio design is based on the replacement percentage of 0% of RCA, and the ratio of RCA to NCA is only changed while the total mass of coarse aggregate remains unchanged, and other materials remain unchanged, so the relevant data in Table 1 is correct.
Point 2: p4, L90, explain "I10 of Q235" clearly like section size and yielding strength etc.
Response 2: I10 of Q235 has a height of 100 mm, a leg length of 68 mm and a web thickness of 4.5 mm. Its yield strength is 423.81 MPa at room temperature.
Point 3: Which standard is used for temperature increasing?
Response 3: According to the fire-resistant grade provided by the fire protection code of Chinese architectural design, the temperature is raised to the set value and then kept constant for one hour.
Point 4: What is the meaning of Fig 7(f) and (g)? reconsider the figures. And analyze more detailly test results and compare with existing test results.
Response 4: Figure 7(f) represents the mass loss ratio of all specimens subjected to the same temperature is averaged, as shown in p10, L179, but due to the author's error, it is written in Figure 7 (g). As shown in p10, L181, Figure 7(g) represents the mass loss ratio of all specimens under the same replacement percentage is averaged. Similarly, due to the author's mistake, it is wrongly written in Figure 7 (h).
Point 5: present how to heat and load the specimens in text clearly. After heating then loading the specimens?
Response 5: As described in P5 and L112, the heated specimens are lowered to room temperature and then loaded.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
The experimental work is consistant, closed to real cases, and follows a rigorous scheme. The analysis of results is clear and efficient, conducted on a large scope of parameters, The conclusions are very intersting and directly usable by engineers. The results are not really surprising and it should be interesting in another paper to compare with the results of other studies conducted on RCA samples, even if generally these samples are not reinforced.
Author Response
Point 1: The experimental work is consistant, closed to real cases, and follows a rigorous scheme. The analysis of results is clear and efficient, conducted on a large scope of parameters, The conclusions are very intersting and directly usable by engineers. The results are not really surprising and it should be interesting in another paper to compare with the results of other studies conducted on RCA samples, even if generally these samples are not reinforced.
Response 1: Thanks for your comments and suggestions, I will make improvements based on your suggestions in the next work.
Author Response File: Author Response.pdf
