Novel Damage Index-Based Rapid Evaluation of Civil Infrastructure Subsurface Defects Using Thermography Analytics
Round 1
Reviewer 1 Report
The paper describes a study aimed at proposing a new numerical index for the assessment of damage in civil infrastructures through thermographic analysis.
With reference to the state of the art, multiple investigation techniques are being studied to detect the inhomogeneities in terms of physical, geometric and structural characteristics of the subsurface. Specific studies are therefore directed towards high-efficiency and high-productivity techniques and procedures / protocols that, in addition to extensive and low-impact investigations, favor monitoring activities allowing the analysis of the evolution of the ongoing distresses.
With respect to these performances, the authors could highlight and quantify the benefits of the described technique in operational terms.
Investigation techniques on concrete structures based on thermographic analysis have been extensively investigated in the past giving satisfactory answers, but they inquire small areas and in very controlled environment.
In order to validate the new damage index the authors should increase the number of samples adopted and a reasonable comparison with traditional techniques of measure should be carried out.
The characteristics of the components and the mix designed adopted should be described more precisely.
There is a lack of comparison between the proposed method and other studies. For the proposal of the new index it is appropriate to compare the experimental values of the mRMSE with standardized indices, usually adopted in contractual documents, such as in Pavement Management Systems.
In summary, the major limitation of the proposed index concerns the limited on field feasibility.
Author Response
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Author Response File: 
Author Response.docx
Reviewer 2 Report
- Lines 73-75: Authors mention the main aim of the paper but it is also suggested to add how this study differs from previous efforts and how it goes beyond the current state of the art.
- Lines 222-223: Please mention what are the challenges occured in field environment.
- Line 226: Authors use Styrofoam blocks to simulated air voids inside concrete beams. However, voids inside concrete beams will not purely consist of 'air' voids. Authors are kindly requested to comment on their view on this further.
- Authors are encouraged to include a 'Next Steps and Future Research' section
Author Response
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Author Response File: Author Response.docx
Reviewer 3 Report
The paper deals with an innovative methodology to quantify the defects detected by means of Infrared Thermography. The approach is of great interest in the field, and I appreciate the adoption of a methodology not involving the ML. Just a pair of suggestion to improve the quality of the submitted paper:
- The concrete samples used in the test should be better described (dimension, procedure of realization, concrete strength, etc), i.e. in a subsection dedicated
- Different concrete strength should be used to better assess the procedure
- The conclusion can be rewritten to summarize more objective parts of the paper, i.e. in a list point
Author Response
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Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
The suggestions were included in the paper, therefore it can be published
