Effect of Rapeseed Imidazoline Addition on the Properties of Lab-Aged 35/50 Pen Grade Bitumen

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This manuscript investigated the rejuvenation effects of two varieties of rapeseed imidazoline on a lab aged 35/50 pen grade bitumen. According to the current manuscript, there are some points the authors need to consider for improving the paper, some detailed comments are shown as below:

1. The authors should write the manuscript in scientific language, there are many colloquial expressions.

2. The Abstract is too broad, it should focus on the key results, findings or conclusions rather than the description of work contents.

3. Lines 68~72, as the motivation statement, it is far from enough.

4. Table 1, what do you mean by 35÷50, 50÷58, -1.5÷+0.7? I cannot understand.

5. Section 2.1.2, the two imidazolines were extracted from rapeseed oil, did the authors consider the cost of rejuvenating agents?

6. All abbreviations and symbols must be defined at the first mention.

7. Figure 2, which is the type 1 or type 2? It should be labelled in the pictures.

8. Table 2, what is the type of rapeseed imidazoline in 35_50_L_R2~R8?

9. Figure 4, please indicate which line is penetration and which line is softening point.

10. Line 210, how did you obtain the range of 608~11.5%? Unbelievable~

11. All the figures in the manuscript must be beautified to make them clearer.

12. Lines 233~234, generally, the boundary value (8%) cannot be determined as the optimum value, because you don't know what happens when it is beyond the boundary. 

13. The conclusion should be refined.

Comments on the Quality of English Language

The authors should write the manuscript in scientific language, there are many colloquial expressions.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The paper presents the results of an experimental study focused on improving the properties of aged bitumen by a rejuvenating treatment. The objectives of the study are well explained, the materials chosen are of interest: 35/50 pen grade bitumen, largely used for road constructions, and rapeseed imidazoline which has good adjuvant properties and is environmentally friendly.  The study is based on two types of rapeseeds imidazoline, at different rates and compares the results used appropriate tests, well described. The results based on the tension curves bring even more proves to sustain the final solution recommended in terms of rate of imidazoline added. The experiments and results bring practical information and are well presented.

 Some minor editing corrections are necessary, mainly to make the figures more clear: the font sizes for  axes labels and graph labels should be increased in all figures.  In figure 4 some supplementary information should be added for the two curves ( blue- softening point, and red- penetration) to be immediately clear how these two characteristics vary  with the rate of imidazoline (explained further in text).

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The authors did not make any changes to Figure 2, types 1 and 2 are still not indicated.

Comments on the Quality of English Language

Minor editing.

Author Response

Dear Reviewer

Thank you again for your comment.

Comments: The authors did not make any changes to Figure 2, types 1 and 2 are still not indicated.

Response 1: A wrong figure was pasted in the manuscript. As suggested, types 1 and 2 are indicated.

Yours sincerely

Robert Jurczak