Finite Element Analysis of Punching Shear of Reinforced Concrete Slab–Column Connections with Shear Reinforcement
Round 1
Reviewer 1 Report
The paper presents a set of numerical simulations using finite elements to reproduce laboratory tests of a reinforced concrete column and slab assembly with shear studs. The article is well structured, with numerous current relevant references. I consider that it represents an interesting contribution to the scientific and engineering community.
I only have the following observations:
From Fiura 12 to 17 there are grouped figures. The authors must indicate them with letters and explain their content in the figure caption.
The authors' consideration that the value suggested by ACI318-19 is conservative compared to the values obtained with the simulations is not reasonable. Comparisons are best made on laboratory test values.
Finally, the references should be adapted to the style of the journal.
Author Response
Please see the attachment. Thank you so much!
Author Response File: 
Author Response.docx
Reviewer 2 Report
Review Report
By finite element method, this study reports the reduction effect of the shear reinforcement on the bending moment.
There are some details that should be paid attention to:
1. The comparison between the use of solid elements and truss elements for shear keys does not show enough details, especially how the interaction between shear keys of solid elements and surrounding concrete is simulated, and the conclusion is not very convincing.
2. It is recommended to show the readers the overall mesh division of the model, and more details about the mesh should be provided, such as the sizes of elements.
3. The selection principle of element size needs to be explained more clearly.
4. The authors did not provide enough details about the CDP parameters, such as the relationship between stress-strain and damage in tension and compression.
5. The results only show the plastic strain PE, and it is recommended to give more comprehensive results, such as the tensile damage factor.
6. In line 189, the “uncorrelated association flow law” should be “non-associated flow law”. This terminology should be corrected.
7. From line 239 to 241, the statement “The dilation angle ? in the CDP 239 model is set to simulate the volume expansion of concrete as a brittle material due to inelastic strain when subjected to tension. A larger dilation angle indicates more brittle concrete.” is suspectable, as the dilation may also happen when geomaterials are subjected to compression.
Comments for author File: Comments.docx
Author Response
Please see the attachment. Thank you so much!
Author Response File: Author Response.docx
Reviewer 3 Report
The paper analyzes very important, and often downplayed in design, issue of punching shear in a slab-column system.
The introduction to the issue presented in the paper is insufficient. The authors should show the methods of modelling the punching issue available in the literature (proposed by other authors) with a critical evaluation of the numerical models obtained by them and their reliability. Only against this background should be presented their own way of modelling, in which the experience of other researchers was used - or not.
The modeled research cases largely reflect reality correctly, so further analysis using them is fully correct.
The article is substantively good, but the method of presenting own additional simulations and authors’ insights and observations requires more detailed description.
I think the authors should split point 3 into two independent ones. In point 3, a comparison of numerical simulations with test results should be presented, as well as a discussion - in a little more detail - of the model’s reliability.
In the new point 4, the authors should show their achievements, i.e., the additional simulations they performed based on the numerical models they made. Please show here (in the main text) the information included in Appendix B, clearly separating the results of the foreign studies and the results of additional own simulations. The description provided in Section 3.3 is not very clear and ambiguous in terms of what was obtained in foreign research and what is the result and novelty resulting from own simulations. Please make this more specific so that the new item 4 contains the "own achievements" in order.
Please change the citation under the figures to the number (from references) in brackets.
Author Response
Please see the attachment. Thank you so much!
Author Response File: Author Response.docx
Reviewer 4 Report
In this paper, the finite element method is used to investigate the effect of shear reinforcement on the moment transfer coefficient, which is a supplement to the existing building design specifications formula and is the significance of this paper. However, there are still many deficiencies in this paper and major revisions are required.
1. Lines 61-63, this paper cites the experimental data of literature 13. Lines 65-66, this article cites the experimental loading method of literature 14, what is the author's innovation in writing this article? Is it just to increase the parameter variables to analyze the bending and shear performance of the plate-column joint?
2. 2.3 Concrete Damage Plasticity Model, the concrete damage plasticity model has been familiar to many scholars, so its description in this section is too verbose and needs to be simplified.
You can refer to the following related articlesï¼›
（1）Wu, etal. Development and testing of hybrid precast steel-reinforced concrete column to H shape steel beam connections under cyclic loading[J]. Engineering Structures, 2020, 211.
（2）Wu, etal.. FEM analysis of the modular prefabricated steel-concrete composite beam-column internal joint under reciprocating action[J]. Steel and Composite Structures, 2021, 41(1): 45-64.
3. 2.4 Calibration of CDP parameters, why only verify dilation angles and viscosity parameters? What about other parameters, such as stress ratio, eccentricity, etc.?
4. Figure 13.-Figure 17., gives the comparison of the failure modes of each specimen. The stress is mainly seen through the stress zone. How is the crack display? Can the author show it?
5. 3.4. Coefficient of the Bending Moment Transferred by the Eccentric Shear Force. How reliable is the bending shear coefficient formula proposed by the author in this section? It is recommended to add relevant content of reliability verification.
6. The conclusion needs to be simplified, and the reference format needs to be the same, standard and standardized.
Author Response
Please see the attachment. Thank you so much!
Author Response File: Author Response.docx
Round 2
Reviewer 2 Report
The authors have addressed all of my concerns.
