Review Reports

Round 1

Reviewer 1 Report

 

1. This paper introduces a bridge foundation scouring detection method using WPR, which provides good reference for practical applications.
2. The paper is written well but not up to the publication standard. A proof reading is recommended to improve the paper and eliminate mistakes and grammar deficiencies. Some examples for improvement are listed here for reference: “antennae” and “antennas” are both used in the paper for several times, please use one of them for consistence; in Fig. 1, both directions are marked “S” (one should be “N”); in Fig. 2, the photo should be taken from the south-west bank according to Fig. 1; in Line 200, what dose “The text continues here.” mean?; in Line 217, “plum-bob” should be “plumb-bob”; etc.
3. In Fig. 5, how the lines are labeled; why “6” lines are different from other lines?
4. The accuracy of the measurements should be evaluated.

Author Response

Many thanks for the excellent comments. We hope we have answered these/corrected adequately.

1. This paper introduces a bridge foundation scouring detection method using WPR, which provides good reference for practical applications.
2. The paper is written well but not up to the publication standard. A proof reading is recommended to improve the paper and eliminate mistakes and grammar deficiencies. Some examples for improvement are listed here for reference: “antennae” and “antennas” are both used in the paper for several times, please use one of them for consistence; in Fig. 1, both directions are marked “S” (one should be “N”); in Fig. 2, the photo should be taken from the south-west bank according to Fig. 1; in Line 200, what dose “The text continues here.” mean?; in Line 217, “plum-bob” should be “plumb-bob”; etc. Many thanks, we have been through the manuscript a lot of times to correct these.
3. In Fig. 5, how the lines are labeled; why “6” lines are different from other lines? We have re-drafted the figure and been clearer in the caption to make these clear.
4. The accuracy of the measurements should be evaluated. Two points here, first some better text on calibrating the radar to measured depths; second, some more discussion in the Conclusions on future work on improving accuracy.

Reviewer 2 Report

Monitoring the riverbed change around the bridge pier particularly during flood events is very important issue and remained unresolved. Therefore, initially I was in favor to approve for publication due to that this was a good attempt to resolve the above problem in bridge engineering but after reading the paper thoroughly, I found some points to be addressed before publication. Following are the major comments.

 

• Deng & Cai (2010) is not in the reference list. Please check all reference in the list and in the text.
• There are three phases’ including Air, Water column and Solid particles motion (sediment motion) at the bed. What is the transition condition between three conditions?
• The most important issue is monitoring the changes at the bed during flood with muddy flow. The biggest changes at the bed and around the bridge piers happen during the flood events with changing flow rate and flow level in which cause to collapse the bridge. How possible to monitor the bed around the pier at the flood event?
• End of page 3 and continuing on page 4, reviewed previous works. There is a jumping between works of year 2000 and year 2020. Although the work by Ebrahimi et al (2020) objective is different form the concept of this work, is there any type of work between 2000 and 2020? So I suggest the comprehensive literature review on the concept of this study.
• The work by Ruffell, A. & Parker, R. 2021. Water penetrating radar. Journal of Hydrology, 597, 126300, in press. https://doi.org/10.1016/j.jhy- 458 drol.2021.126300 is not accessible. What is difference between this paper and above paper? I am wondering for overlapping of the materials and findings.
• Figure 11 shows some snapshots of the bed topography. As the flow moves from south to north direction, there is no evidence of having maximum depth of scour hole at the upstream of the piers. Please check and clarify. How verify the results from WPR? Is there a comparison?

Author Response

• Many thanks for these detailed review comments. We hope our revisions and explanations (below, italics) are sufficient, indeed have improved the work.
• Deng & Cai (2010) is not in the reference list. Please check all reference in the list and in the text. Reference added and others checked.
• There are three phases’ including Air, Water column and Solid particles motion (sediment motion) at the bed. What is the transition condition between three conditions? We added a short section (lines 237-239 on these phases and their radar imaging.
• The most important issue is monitoring the changes at the bed during flood with muddy flow. The biggest changes at the bed and around the bridge piers happen during the flood events with changing flow rate and flow level in which cause to collapse the bridge. How possible to monitor the bed around the pier at the flood event? We have added some short sections of text, and specifically Table 1 and it's caption to discuss the problems of flood events, needing a higher-powered boat, or suspension of antenna above the water.
• End of page 3 and continuing on page 4, reviewed previous works. There is a jumping between works of year 2000 and year 2020. Although the work by Ebrahimi et al (2020) objective is different form the concept of this work, is there any type of work between 2000 and 2020? So I suggest the comprehensive literature review on the concept of this study. Thanks for this - something we had not spotted, bar the 2007 reference - so we checked the literature and whilst there is a lot on water radar, there is a gap in these years. Fell out of favour perhaps.
• The work by Ruffell, A. & Parker, R. 2021. Water penetrating radar. Journal of Hydrology, 597, 126300, in press. https://doi.org/10.1016/j.jhy- 458 drol.2021.126300 is not accessible. What is difference between this paper and above paper? I am wondering for overlapping of the materials and findings. Correct doi inserted - these change we note. The Ruffell & Parker work has about 1/6 on scour, and in review only.
• Figure 11 shows some snapshots of the bed topography. As the flow moves from south to north direction, there is no evidence of having maximum depth of scour hole at the upstream of the piers. Please check and clarify. How verify the results from WPR? Is there a comparison? We have annotated Figure 11 to show our evidence of upstream scour and the location of the scour: this comment by Reviewer 2 is great, and got us to re-visit this figure, which we all agree is improved. Verification would come with drainage of the river and/or the next scour event(s).