Comments on abstract, title, references

Comments on abstract,

The experimental results showed a reduction in unit weight. The sand replacement harmed the concrete mechanical properties at varying rates. The experimental results proved that plastic waste can be disposed of by specific ratios and therefore, can be effectively applied in industrial usage.

Please replace the above section by the new section below:-

The experimental results showed a reduction in unit weight, the sand replacement harmed the concrete mechanical properties at varying rates, and proved that plastic waste can be disposed of by specific ratios and therefore, can be effectively applied in industrial usage.

Comments on references:-

• correct the reference No.31 by delete “5 -

[31] S. M. Hama and N. N. Hilal, “5 - Fresh properties of concrete containing plastic aggregate,” in Woodhead Publishing Series in Civil and Structural Engineering, F. Pacheco-Torgal, J. Khatib, F. Colangelo, and R. B. T.-U. of R. P. in E. C. Tuladhar, Eds. Woodhead Publishing, 2019, pp. 85–114.

**Dear Author, you should add recent references on the subject of the research from2018 until 2020

Comments on introduction/background

I have no comment because the introduction was written in a good method.

Comments on methodology

*Dear Author, check table 1, row 6 are you sure from this Absorption % of PET value? because of the absorption of PET = ZERO OR small value.

****This test was applied to show the effect of fire on the concrete samples by using a direct flame on specimens.

The examination was done according to any specification,? please mention it.

Comments on data and results

*Table 4:cheek this Velocity (m/s)I think the velocity (UPV) measured by( km/sec).

-** in Fig. 12:Reduction in dardened unit weight should be corrected to a reduction in dry unit weight .

***Figure 13 does not show any relationship between the mechanical properties of the PET concrete???

what are you meaning by these words?

****Figure 18 shows the forms of specimen before and after 300 s of exposure to the flame.

why you used 300 sec according to what ?

*Fig. 21: Pictures of smoke rising from samples

according to this Fig.thats mean this work, not Eco friendly

you can added as a reference

Comments on discussion and conclusions

The discussion and conclusions are well written and clear

in item 4.2 Recommendations point 7.

yes below paper discusses the problem

Influence of PET wastes on the environment and high strength concrete properties exposed to high temperatures Ibrahim H. Alfahdawi , S.A. Osman a, R. Hamid , Abdulkader Ismail AL-Hadithi