Finite Element Simulation of FRP-Strengthened Thin RC Slabs
Round 1
Reviewer 1 Report
This article is mainly focused on modeling and simulations using FEM method. Experimental results from other sources were used. The main problem is the symmetrical conditions that were used in the analysis (Section 2.1). I do not understand why the symmetrical condition was used in the z-direction. The composite tape was attached to the bottom of concrete slab, as shown in Figure 6. Even if the composite tape were attached to top and bottom of slab, yet the symmetrical boundary condition should be applied to the top model as shown in Figure 2. Maybe, I am missing something here. I strongly suggest authors to make it clear in the model description.
The other comments is related to the name two-point bending test. We have three-point or four-point bending test. This test is four-point test. I suggest replacing two-point with four-point bending test.
My other comment is related to the different types of composite studied in section 3.3 Parametric study. I am not sure if you can use the balsa wood composite which is mainly sandwich structures in this application.
Author Response
Please see attached ...
Author Response File: 
Author Response.docx
Reviewer 2 Report
Taken into account all the following shortcomings mentioned, this paper needs to be revised.
1. In combination with the full text, abstract does not give a brief description of the author's views, key contents and research results of the article.
2. The number of keywords is too large. There are usually about 5 keywords. It is not necessary to be too many. It is recommended to delete them.
3. The second paragraph of introduction introduces the relevant research, which is too lengthy and tedious, and it is suggested to delete it.
4. The use of arrows in Figure 1 is not standard, and the auxiliary line needs to be modified. Please refer to relevant standards; B in Fig. 2 is vague and unclear; The picture a in Fig. 6 is not clear enough, and it is suggested to adjust the shooting angle so that the reader can observe it more intuitively. The description of failurecriteria in 14.3.2 does not provide a detailed analysis and explanation of the causes of the picture, so the existence of the picture is not significant.
5. The title of Table 2 has format error and is not written in the middle.
6. In3.3.2, the analysis of figure 8-11 is too brief. It is suggested to add text description and pay attention to analysis.
7. In this paper, the research significance and application of this study should be explained in detail, as well as the guiding significance of the experimental results for future research.
Comments for author File: Comments.doc
Author Response
Please see attached ..
Author Response File: Author Response.docx
Reviewer 3 Report
The manuscript explored the flexural behavior of high-strength thin slabs externally strengthened with fiber-reinforced polymer laminates through a numerical simulation. It is well written and thus I recommend publication of this manuscript with some minor questions and suggestions:
1 Materials and Methods part
a) What is the reinforcement method in the laminate? Are the fibers aligned in accordance with the load paths? Fibers are randomly located?
b) Did the authors try to use different mesh density to make sure the results are converged?
c) It would be better if the authors could provide more details about the materials model part. How did the authors set up the material properties? Only the different compressive and tensive modulus were set? The elastic part and the Poisson's ratio are assumed to isotropic? What if the laminate is orthotropic? What if the orientation of fibers would influence the elastic part?
d) Line 161, the equation to calculate the Modulus of elasticity is not clear enough. Firstly, the letter c should be subscribed. Secondly, it only takes the square root of 70. We do not need to consider the unit MPa. Please describe this part more clearly.
e) Did the authors write subroutines for the ANSYS simulation?
2) Results and Discussion part
a) The simulation results compare well with the test results. This is great. It would be better if the authors could talk about more about the most possible reasons for the small differences.
b) The authors mentioned that “Since concrete compressive strength is relatively high, concrete crushing did not occur in any of the modeled specimens.” What is the practical use of the simulation for the concrete crushing analysis?
Comments for author File: 
Comments.pdf
Author Response
The authors would like to thank the Editor and Reviewers for their thorough review and comments that enhanced the quality of the manuscript. The paper has been revised to incorporate the comments and suggestions made by the Reviewers. The manuscript has been modified according to the recommendations as detailed in the attached file and the changes arising from this review are highlighted in yellow and strikethrough in red in the revised manuscript.
Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
Thanks for the clarification. Now it sounds reasonable. Please make sure to mention that the composite strip partially covers the width of the beam, as shown in Figure 6. Without mentioning that, it might cause confusion for the readers.
Author Response
Thank you for addressing this point. A clarification sentence was added to L98: (the CFRP sheet partially covered the slab’s bottom width)
Reviewer 2 Report
This study aims to investigate the flexural behavior of high-strength thin slabs externally strengthened with fiber-reinforced polymer (FRP) laminates through a numerical simulation.
According to the suggestion before, the authors have revised this article including the language such as grammar and format, interpunction, the authors also gave the reasonable expression about the questions.
The manuscript can be accepted.
Author Response
Many thanks.
Reviewer 3 Report
The reversion is accepted.
Round 3
Reviewer 1 Report
Thanks for clarification and corrections.
Reviewer 2 Report
The manuscript can be accepted.
