Effect of Aging and Moisture Damage on Fatigue Cracking Properties in Asphalt Mixtures
Round 1
Reviewer 1 Report
The paper focus on the effect of aging and moisture damage on fatigue cracking properties in asphalt mixtures. The topic is quite interesting. However, some minor revisions are required before accepted for publication. Please revise the manuscript as per the recommendations given. This paper requires thorough proofreading. Please check the entire paper for the grammatical errors.
- Lack of discussion on the findings. Authors just reporting their findings.
- The conclusions of the manuscript need to enhance a little.
Author Response
Point 1 : Lack of discussion on the findings. Authors just reporting their findings.
Point 2 : The conclusions of the manuscript need to enhance a little.
Response 1, 2 : The conclusion was enhanced.
Author Response File: 
Author Response.docx
Reviewer 2 Report
1、Twenty hours is generally chosen as a long-term ageing indicator according to AASHTO. Why did you choose 48 hours, 96 hours and 192 hours as indicators and what was the basis for the choice. Please provide a reference.
2、The authors argue that abnormal climate change directly or indirectly causes deterioration of road pavements, but do not provide sufficient theoretical justification. The authors suggest that South Korea experienced extreme weather conditions and increased pothole damage in a given year but pavement distress is in fact influenced by a number of factors. Please provide sufficient evidence to prove that there is a sufficient link between the climate change and the pothole damages.
3、The authors have chosen HMA and WMA mixture asphalt with specific parameters as the experimental material, why did they choose these two asphalt materials? Is there any suitability for other asphalt applications? Please provide a reference.
4、The conclusions are not strong. It is clearly that “as the service period progressed, the fatigue life due to aging gradually increased while the change in fatigue life due to moisture damage gradually decreased”. However, ageing is a continuous process and moisture damage is an intermittent process, whether ageing can exacerbate moisture damage and conversely whether moisture damage can accelerate the rate of asphalt ageing? Have these factors been considered in the conclusions.
5、Line 439 There is a typo here.
Author Response
Point 1 : Twenty hours is generally chosen as a long-term ageing indicator according to AASHTO. Why did you choose 48 hours, 96 hours and 192 hours as indicators and what was the basis for the choice. Please provide a reference.
Response 1 : The reference for selecting long-term aging time was added to Chapter 3.
Point 2 : The authors argue that abnormal climate change directly or indirectly causes deterioration of road pavements, but do not provide sufficient theoretical justification. The authors suggest that South Korea experienced extreme weather conditions and increased pothole damage in a given year but pavement distress is in fact influenced by a number of factors. Please provide sufficient evidence to prove that there is a sufficient link between the climate change and the pothole damages.
Response 2 : In the introduction, additional data on the link between climate change and pothole damage were prepared. (Figure 1)
Point 3 : The authors have chosen HMA and WMA mixture asphalt with specific parameters as the experimental material, why did they choose these two asphalt materials? Is there any suitability for other asphalt applications? Please provide a reference.
Response 3 : The asphalt binder used in HMA and WMA has the same performance as PG 64-22 or PG 64-16, so both mixtures have the same co-performance. However, since WMA involves mixing and commitment at a temperature about 30°C lower than HMA which uses additives, its short-term and long-term aging are expected to be different from those of HMA. The results of the elastic modulus and fatigue crack experiment revealed the characteristics of the asphalt mixture to vary with the aging temperature and time of the HMA and WMA. In particular, in Korea, there is a growing interest in construction methods that produce and construct about 30℃ lower than HMA like WMA, for carbon neutrality. Therefore, this can be used as a basic study on the changes in the properties of the asphalt mixtures with HMA and WMA aging.
Point 4 : The conclusions are not strong. It is clearly that “as the service period progressed, the fatigue life due to aging gradually increased while the change in fatigue life due to moisture damage gradually decreased”. However, ageing is a continuous process and moisture damage is an intermittent process, whether ageing can exacerbate moisture damage and conversely whether moisture damage can accelerate the rate of asphalt ageing? Have these factors been considered in the conclusions.
Response 4 : The conclusion was enhanced.
Point 5 : Line 439 There is a typo here.
Response 5 : The typo was corrected.
Author Response File: Author Response.docx
Reviewer 3 Report
please see the attached file for the review comments.
Comments for author File: Comments.docx
Author Response
Point 1 : The main specifications of the used bitumen for manufacturing HMA and WMA should be illustrated in a Table.
Response 1 : Test variables and designation of specimens added. (Chapter 2.1 )
Point 2 : The sieve size and gradation of aggregates and their mechanical and physical properties should be add to the revised version in a separate Table.
Response 2 : The material properties of aggregates added. (Chapter 2.1 )
Point 3 : What is the reason of extra cutting and coring of the final samples from the pre-manufactured cylindrical asphaltic mixtures? Please discuss and clarify more.
Response 3 : The reason of extra cutting and coring of the final samples added. (Chapter 2.3)
Point 4 : The number of Refs. In this article is not sufficient. The effect of aging and also cracking study of asphaltic mixtures and bituminous materials has also been investigated in recent years such as (Fatigue & Fracture of Engineering Materials & Structures,(2019), 42(7), 1609-1621.; Applied Science,(2021), 11(7),3013.; Applied Science,(2021), 11(11),5094.; Theoretical and Applied Fracture Mechanics,(2020), 110, 102800.; Engineering Fracture Mechanics,(2018) 190, 245-258.; Construction and Building Materials, (2020), 234, 117365.; International Journal of Pavement Engineering, (2019), 1-12.; Engineering Fracture Mechanics,(2019) 216, 106496.; Theoretical and Applied Fracture Mechanics, 110, 102801.; Construction and Building Materials, (2021) 276, 122181). The mentioned works can be reviewed and considered in the revised version.
Response 4 : Added the number of Refs. and revised the introduction.
Point 5 : It is suggested adding error bars to the graphs and charts of Figs. 11 to 15.
Response 5 : Added the error bars (Figure 12, 13)
Author Response File: Author Response.docx
Round 2
Reviewer 2 Report
The revised version is much better than the original one. However, the introduction part is recommended to expand before it can be published. The authors can refer to Journal of Cleaner Production 263 (2020): 121447; ACS applied materials & interfaces 9.46 (2017): 41014-41025.
Author Response
Thanks for your review.
I added your recommend Refs. in the introduction.
Author Response File: Author Response.docx
Reviewer 3 Report
I recommend publishing this revised version in the journal.
Author Response
Thanks for your sincere and correct review.
