Analysis of Modulus Properties of High-Modulus Asphalt Mixture and Its New Evaluation Index of Rutting Resistance
Round 1
Reviewer 1 Report
The paper is devoted to the analysis of the high-modulus asphalt mixture. It presents the laboratory, in-situ and numerical test results. The latter ones are of the lowest quality. I insist on their better description. In the current form, they lack a proper description, which makes them impossible to be reproduced by the other researchers.
Below, I present a number of specific remarks. Besides, the proofreading is necessary. Particularly, the punctuation is incorrect very often.
Line 13: Clarify the abbreviation "PE" before its first use.
Line 14: Capital "S" in "Styrene-butadiene-styrene(SBS)" is not necessary here. Add a space between "styrene" and "(SBS)".
Line 22: Explain briefly, why the temperature of precisely 54 degs was selected for this index.
Line 37: Change the capital letter "T" to the small one in "The requirement for...".
Add missing spaces in the whole manuscript, e.g. in:
Line 40: Add a missing space in "pavement[4, 6]".
Line 45: Add a missing space in "design[2]".
Line 49: Add a missing space in "HMAM[2]".
Line 55: A period should be removed in "asphalt concrete.)".
Line 63: Explain the abbreviations before their first use - "PRS and PRM".
Line 70: Add references after "road observation and laboratory studies of HMAM".
Line 143: Replace "to combine with" with "to combine it with".
Table 3: Use a capital letter "A" in "adhesion degree" to be consistent with the rest of the content.
Line 164: Add a reference after "French EME method".
Line 167: Add a reference after "Superpave method".
Table 4: Provide the units.
Line 187: Why these temperatures and frequencies were selected?
Equations and their textual descriptions should be formatted in the same manner.
Line 225: What is the specific value of the "uniform vertical load" used in the test?
Figure 3: Figure is incomplete. What is the thickness of the subbase? How the subgrade was modeled? What are the kinematic boundary conditions applied in the test?
Line 232: Change to the small letter "m" - "pavement Mechanical response".
Line 234: Clarify, why this modulus "was chosen as the modulus input parameter for the calculation". How is it justified with the assumption on the linear elasticity of the domain?
Equation 4: It is misleading to use similar symbols (deltas with different subscripts) to describe quantities of different type.
Line 241: How the creep modulus S_mi is assumed? Without the knowledge on its assessment the results are meaningless.
Line 248: There is an inconsistency of the symbols used in the inline formula and Equation 4. Why C_m is assumed to be equal to 1?
Line 254: Correct "Figure. 4 present".
Line 284: Correct "The may".
Figure 10: The captions are reversed probably.
Figure 10b: Correct the y-axis label. At which point the vertical stress was calculated?
Line 375: What does it mean -"can improve the stress"?
Table 7: What is S_mi value?
Line 383: What does it mean - "can improve the force"?
Lines 446 and 22: Inconsistency in the presented temperature.
Author Response
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Author Response File: 
Author Response.pdf
Reviewer 2 Report
The introduction of the article discusses the importance of high modulus asphalt mixtures (HMAM) as an effective material to enhance the rutting resistance and durability of asphalt pavements. It highlights the three ways of preparing HMAM and the factors affecting their performance on the road. The introduction also mentions the extensive research conducted on the road performance and mechanical properties of HMAM. However, it lacks a clear statement of the research gap and the specific objectives of this study. To improve the introduction, it could be revised to include a clear statement of the research gap and the specific objectives of this study, which are to investigate the correlation between the rutting resistance of different types of HMAM and their modulus properties, propose reasonable modulus evaluation indicators, and analyze the rutting resistance mechanisms of different materials. This would provide a clearer context for the study and help the reader understand its significance.
here are some suggestions for revisions:
The language could be made more concise and precise in places.
The discussion could benefit from more contextualization, explaining why the findings are important and what they might mean for future research or practice.
The text could benefit from clearer transitions between different sections and paragraphs, to help readers follow the argument more easily.
It might be helpful to include more discussion of the limitations of the study and how they might affect the interpretation of the results.
The text could benefit from more attention to proofreading and editing, to eliminate errors and inconsistencies.
Author Response
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Author Response File: Author Response.pdf
Reviewer 3 Report
This study focused on proposing new evaluation indicators of rutting resistance for high-modulus asphalt mixtures and analyzing the rut-resistant mechanisms. The research topic is towards the practical application and very meaningful. Some good results have been reached, but there are still some issues that need be addressed before consideration for publication. Some of the comments are drawn as follows: *It needs to have the manuscript proofread for the language improvement. *As introduced, the authors choose two different high-modulus agents to modify asphalt binders and also knew their dissolution and dispersibility issues, but no evidences can be found to support the applicability of the modified asphalt binders. * Figures 4 and 5: The differences of dynamic modulus and viscoelastic component among these five mixtures cannot be directly found from the separate figures. It is advised to add a table for their comparisons. *Some figures are not clear. *It would be better to refine the conclusions to be more concise.
Author Response
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Reviewer 4 Report
In this paper, the authors investigated the dynamic modulus of high-modulus asphalt mixtures prepared by different materials and a new index for the evaluation of rutting resistance based on modulus was proposed. Overall, the presentation and layout of this manuscript are satisfactory. The interpretations and conclusions are reasonable. More specific comments are listed below to improve this manuscript.
1. Line 4, one author's detailed information is missing, please pay attention to supplement.
2. Line 188, the test temperatures and frequencies are different from the discussion part, please check and correct.
3. Fig.4, Fig.5 & Fig.10, please adjust the font size in the figure to be consistent.
4. Line 311, the author mentioned that ‘It can be observed that all the mixtures passed the 3000 cycles/ mm required by the Chinese specification JTG F40-2004’, however, the requirements for dynamic stability indicators are diverse for different mixes, and the applicability of the specification is debatable, please check and correct.
5. Line 372, what is the meaning of Q value, more explanation should be added.
6. The abstract and conclusions are lengthy. Please refine to show the main contribution of this manuscript.
7. The following related researches could be reviewed: 10.1016/j.jclepro.2022.134123, 10.1016/j.conbuildmat.2021.122389
8. There are some typos in the paper. Some illustrations are listed as follows:
a) Table 2 & Table 3, ‘g/cm3’ should be ‘g/cm3’
b) The title of section 2.3.2
c) Line 233, ‘Mechanical response’ should be ‘mechanical response’
d) Line 255, ‘Figure. 4 present’ should be ‘Figure. 4 presents’
Author Response
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Round 2
Reviewer 1 Report
In my opinion, the modifications of the manuscript are sufficient enough to recommend the publication of the manuscript. However, I still have some remarks concerning the numerical part:
- explain, why the Bailey-Norton creep model was used and describe it in a more detailed manner (e.g. provide the time-stepping algorithm),
- explain the inconsistency in the mesh density between Figures 3, 4 and 13;
- comment the reliability of the numerical results (particularly those presented in Fig. 13),
- Poisson ratio is dimensionless, correct it in the manuscript.
Author Response
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Author Response File: Author Response.pdf
Reviewer 2 Report
Introduction section
Here are some suggested revisions for the introduction:
- Specify the focus of the study earlier on by mentioning that this paper presents a new evaluation index of rutting resistance for high-modulus asphalt mixtures.
- Clarify why high-modulus asphalt mixtures are ideal for long-life pavements earlier on in the introduction.
- Provide more background on the preparation methods of HMAM, such as using low penetration grade asphalt, natural asphalt, and adding high modulus modifiers based on polyolefins, earlier in the introduction.
- Provide a clearer summary of the key findings of previous studies on the road performance and mechanical properties of HMAM, including their rutting resistance, fatigue resistance, and low-temperature performance, earlier in the introduction.
- Provide a clearer link between the stress-strain response characterized by the dynamic modulus and the rutting resistance of HMAM.
Results section
Overall, the section seems well-written and clear. However, there are a few things that could be revised to improve the clarity and readability:
- The section could benefit from an introductory paragraph that briefly summarizes the main findings of the study and provides some context for the results and discussions that follow.
- The figures should be referred to in the text before they are presented. For example, the text could say "Figure 5 shows the variation of dynamic modulus with loading frequencies under different temperatures for the five mixture types."
- The caption for Figure 5 could be revised to be more descriptive. For example, it could say "Variation of dynamic modulus with loading frequency for the five asphalt mixture types at temperatures ranging from -10°C to 40°C.
Author Response
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Author Response File: Author Response.pdf
Reviewer 3 Report
After checking the revised manuscript, the authors have well addressed the proposed comments. The responses to the comments are reasonable. Therefore I recommend accepting the manuscript at current version.
Author Response
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