Evaluating the Field Performance of Permeable Concrete Pavers
Round 1
Reviewer 1 Report
This paper communicates (the benefits) of PICPs and is providing evidence of their long term (10 years) field performance in Australia. Since, as stated by the authors, permeable interlocking concrete pavement systems (PICPs) have not translated into widespread adoption in Australia it is important to have data from practice for general guidelines on design, construction and maintenance. Unfortunately, figures are missing and misnumbered and general mistakes in references make the paper unreadable in this form to review. Several questions are raised by reading the text that will help the authors view their work with more criticism which is needed since the paper reviewed more or less one product(type) and builds strongly upon 1 reference. I have the feeling (based on the email addresses) that the authors are new at science and hope this will not discourage them for taking a step into the scientific publication world but this will contribute to better critical and complete papers. Looking forward to see this valuable data and conclusions in a readable format.
Comments for author File: 
Comments.pdf
Author Response
Response to Reviewer 1
Permeable pavement is an important approach to reduce runoff from urban impervious surfaces. The infiltration rate was employed to evaluate the infiltration capacity using the SRIT and SWIFT tests. In addition, the influence of some factors was explained and compared. The authors had carried out lots of filed tests which were really appreciated. However, I have several serious problems with the document as it stands and it will need very serious revision if it is to be accepted.
Reviewer Query 1: The expressions lack of standardization, such as the references in abstract in lines 15-18, the number of the equation in lines 151, line 318, line 352, etc., please check and correct other places, including the spelling?
Author response: References in the abstract have been removed.
the number of the equation in line 151 has been corrected.
line 318 – Table 1 should be Table S1
line 352 – Number of locations in Table 8 should be 8 not 9.
Reviewer Query 2: In line 183, “as they a similar non-porous paver systems”, please correct?
Author response: corrected to
“as they are similar non-porous paver systems.”
Reviewer Query 3: In line 232, the contents in ‘Table 1’ is not appropriate for the expression here.
Author response: The table mentioned should be Table 1
Reviewer Query 4: The number and content of the figure is not matching and integrity, such as in lines 259 and 262, etc.
Author response: This has been corrected in the revised manuscript, Table 1 should be Table S1
Reviewer Query 5: Where is the ‘Section 4’ in line 235?
Author response: This has been corrected in the revised manuscript, should be section 3.3.
Reviewer Query 6: From my opinion, there is no relevant evidence in this study to verify the relationship between the results of SRIT and SWIFT tests, as the statements in lines 16, 17.
Author response: A relationship between SRIT and SWIFT was developed by Lucke [14]. That procedure was verified in this study. The relevant sentences were modified as follows
“A strong correlation was found between the results of the two tests in a previous study, which was verified in this study.”
Reviewer Query 7: The purpose of this study is not so clear to the readers although the infiltration rate was obtained and investigated, the evaluation was not quite sufficient?
Author response: This study was the first to collect data in Sydney Australia from actual field installations of PICPs and assess their long term performance. Previous studies attempted to mimic long term performance in the laboratory or were an assessment of a limited number of PICPs field location. The results of this study challenges the notion that common exist that PICPs quickly become clogged and lose their infiltration capacity. The purpose of the study was rephrased as follows:
“The purpose of the field tests is to gauge the long term in-situ performance of PICPs and examine the results for its implications for design. Assessment of field installation of PICPs that exist under a range of conditions such as topography, insitu soil, vegetation and moisture conditions, and load and operating conditions were made. There is a perception that PICPS quickly lose their infiltration capacity and this has held back their widespread application. The results of this study will challenge widely held notions and inform regulatory authorities and designers of the actual situation.”
Reviewer Query 8: There are two ‘Section 3.1’ and ‘3.2’.
Author response: This has been corrected in the revised manuscript, the last two were corrected to section 3.3 and 3.4.
Reviewer Query 9: In Figure 10, the label is short.
Author response: The caption for the figure was rewritten in the revised manuscript to provide more information i.e.
“Probability of the infiltration rate being exceeded based on all data collected in this study and that from Lucke et al. [14].”
Reviewer Query 10: In line 415, ‘The infiltration rate of PICPs collected from filed tests varied over a relatively high range from 125 to 25,000 mm/h under various conditions.’, where is the source of the data ‘25,000 mm/h’?
Author response: Additional wording was added in the revised manuscript to make this clear i.e.
“The later was a measurement obtained in this study.”
Reviewer Query 11: When making the comparisons, it can be better presented the resulted obtained by the authors and then compared with results obtained by Lucke et al. [14]
Author response: The text of the revised manuscript was rewritten in this way.
Reviewer Query 12: The explanation of saturation was studies sufficient, but the relationship between this part and variability and the research aim is not quite fitness, please consider.
Author response: Apart from those discussed in earlier sections of the manuscript, another possible course of reduced infiltration of PICPs and scatter in results seen in Figure 2 is the degree of saturation of the subgrade, base course and bedding layer and ground beneath the PICPs. To examine this aspect and to observe the reduction in infiltration possible over extended periods of rainfall an examination of the impact of saturation was undertaken. The test show that the drop in infiltration can be as high as 63%, possibly explain some of the scatter observed in Figure 2. The following was added to the revised manuscript.
“One of the concerns of PICPS is the expected reduced infiltration rates over periods of extended rainfall. This can occur as the subgrade, base course and bedding layer and ground beneath the PICPs become saturated.
The test show that the drop in infiltration can be high, and possibly explain some of the scatter observed in Figure 2.”
Reviewer Query 13: The literature introduction is quite inappropriate in line 30, ‘This study focusses upon PICPs, for which significant results have been obtained, for example, in the US [3-4]; Canada [5-6]; Europe [7-11] and Australia [12-15].’
Author response: We have revised the sections 1 and 2 of the revised manuscript to consolidate the literature review to more clearly present current relevant information on PICPs. We have also revised the relevant sentence the reviewer mentioned.
Author Response File: Author Response.pdf
Reviewer 2 Report
Permeable pavement is an important approach to reduce runoff from urban impervious surfaces. The infiltration rate was employed to evaluate the infiltration capacity using the SRIT and SWIFT tests. In addition, the influence of some factors was explained and compared. The authors had carried out lots of filed tests which were really appreciated. However, I have several serious problems with the document as it stands and it will need very serious revision if it is to be accepted.
- The expressions lack of standardization, such as the references in abstract in lines 15-18, the number of the equation in lines 151, line 318, line 352, etc., please check and correct other places, including the spelling?
- In line 183, “as they a similar non-porous paver systems”, please correct?
- In line 232, the contents in ‘Table 1’ is not appropriate for the expression here.
- The number and content of the figure is not matching and integrity, such as in lines 259 and 262, etc.
- Where is the ‘Section 4’ in line 235?
- From my opinion, there is no relevant evidence in this study to verify the relationship between the results of SRIT and SWIFT tests, as the statements in lines 16, 17.
- The purpose of this study is not so clear to the readers although the infiltration rate was obtained and investigated, the evaluation was not quite sufficient?
- There are two ‘Section 3.1’ and ‘3.2’.
- In Figure 10, the label is short.
- In line 415, ‘The infiltration rate of PICPs collected from filed tests varied over a relatively high range from 125 to 25,000 mm/h under various conditions.’, where is the source of the data ‘25,000 mm/h’?
- When making the comparisons, it can be better presented the resulted obtained by the authors and then compared with results obtained by Lucke et al.
- The explanation of saturation was studies sufficient, but the relationship between this part and variability and the research aim is not quite fitness, please consider.
- The literature introduction is quite inappropriate in line 30, ‘This study focusses upon PICPs, for which significant results have been obtained, for example, in the US [3-4]; Canada [5-6]; Europe [7-11] and Australia [12-15].’
Author Response
Response to Reviewer 2
This paper communicates (the benefits) of PICPs and is providing evidence of their long term (10 years) field performance in Australia. Since, as stated by the authors, permeable interlocking concrete pavement systems (PICPs) have not translated into widespread adoption in Australia it is important to have data from practice for general guidelines on design, construction and maintenance. Unfortunately, figures are missing and misnumbered and general mistakes in references make the paper unreadable in this form to review. Several questions are raised by reading the text that will help the authors view their work with more criticism which is needed since the paper reviewed more or less one product(type) and builds strongly upon 1 reference. I have the feeling (based on the email addresses) that the authors are new at science and hope this will not discourage them for taking a step into the scientific publication world but this will contribute to better critical and complete papers. Looking forward to see this valuable data and conclusions in a readable format.
Reviewer Query 1:
No reverences in the abstract please
Author response: All references have been removed
Reviewer Query 2: This paper communicates the benefits of PICPs o Only the benefits?
Author response: In the revised manuscript the sentence was rewritten as
This paper communicates the actual performance of PICPs in the field by providing evidence of their long term efficiency.
Reviewer Query 3: L41 The majority of these results were obtained through the testing of PICPs constructed with non-porous pavers, which rely on water infiltration through joint spaces. This cur- rent study will primarily focus on PICPs comprised of porous pavers that create a fully permeable surface.
No different name in Australia for this type? So you have to make that clear in lines as done at l89, l100, l105 and more…
Author response: The porous and non-porous terms term were added to the PICPs. In the introduction section (section 1) the use of PICPs was qualified in this way.
In this study the results were for HydroSTON [22] and Ecotrihex [23] PICPS. HydroSTON [22] are porous pavers and Ecotrihex [23] are non-porous pavers. This was made clear in the revised manuscript (see section 2.1) i.e.
HydroSTON [22] and Ecotrihex [23] are porous pavers and non-porous pavers respectively.
In subsequent occasions we have not included the terms porous/non porous in PICPs.
The paper mentions the data of Lucke [24] extensively. In the first occasion it was made clear the data of Lucke [14] was for non-porous pavers. In section 3.1 of the revised manuscript we added the following.
Lucke [14] data were collected for non-porous PICPs.
In subsequent occasions this was not included.
Reviewer Query 4: L51 A wide range of PICPs products are available such as per- meable concrete, ceramics and solid pavers.
Ceramics is not concrete, still you call it PICPs?
Author response: There are indeed a wide range of permeable pavement and difficult to classify them under one name. We have chosen to take a more broader approach in classifying them as PICPs. It is not important to name ceramics separately so we have deleted it from the revised manuscript.
Reviewer Query 5: L53 However, their adoption in Australia has been slow o Any numbers to back this up? Is there an inventory of locations in Australia? Note that if you compare it to Europe some countries have ‘slow implementation or none’ compared to other countries
Author response: A new reference has been added.
Johnson, T., King, R. Experience with Pervious Paving. 6th Australian National Conference on Urban Water Management: New Frontiers into the Next Decade, 13-16 April 2021, Held virtually
Reviewer Query 6: L55 is this a representative example for the situation in Australia? In a scientific paper it would be nice to have some more evidence of ‘often depends and often rejected’
Author response: The rebate offer by Ku-ring-gai Council in NSW Australia was provided to demonstrate the encouragement that exists. It was not meant as representative and in fact this Council is one of the few that provides encouragement. It was merely meant to demonstrate that despite encouragement provided in some localities uptake of PICPs has been slow.
Reviewer Query 7: L77 if SWIFT test is referenced, lets give SRIT also a reference…
Author response: Reference was added to SRIT test in the revised manuscript.
Reviewer Query 8: L92 no figure S1 also not in appendix/word file
Author response: Figure S1, because of its size it was placed on last page of the supplementary material.
Reviewer Query 9: Figure 1: these are old studies, please update. First one in legend did more in 2019 for example with more data, making your graph more interesting. Some points can not be seen maybe (not sure about age of 7 years for example) how many points does the graph show and any view on outlines as Sanudo at year 10 with 3000 mm/h? Any circumstances that clarify this?
Author response: Boogaard and Lucke [17] conducted testing under the FIST method where infiltration measurements were taken when large sections of pavements were indundated with water. This is different to other data (except Boogaard et al. [10]) shown in Figure 1 where infiltration was carried out under the traditional SIRT method.
The results of Boogaard and Lucke [17] ranged between infiltration of 21-503 mm/hr and pavement age of 2-8 years. If plotted they would all virtually lie on the x axis given the scale of the y axis. This will overlap and clog the data presented in figure 1 which the reviewer points out is already a problem. Plotting the data gives not additional gain and in fact reduces the quality of Figure 1. We have chosen to mention and describe the data in the text since i.e.
Boogaard and Lucke [17] conducted 13 field test in Netherlands using the full-scale infiltration testing (FSIT) method where infiltration measurements were taken when large sections of pavements were inundated with water. The results of Boogaard and Lucke (2019) ranged between infiltration of 21-503 mm/hr and pavement age of 2-8 years. If plotted in Figure 1 the data would all virtually lie on the x axis given the scale of the y axis.
Sañudo-Fontaneda et al. [13] data at 10 years appear to plot high in Figure 1 but not so in Figure 3. In the later the data plots lower than many of the data.
Reviewer Query 10: L113, S1 and T1 is missing
Author response: Figure S1, because of its size was place on last page of the supplementary material. Table 1 in the supplementary material was relabelled Table S1.
Reviewer Query 11: L117 not the right way of referencing
Author response: The reference was corrected.
Reviewer Query 12: L114 ‘Most of 114 the tests were conducted at sites where HydroSTON pavers’ o Be careful then to talk about PCIP in general, when It seems you tested 1 system … and some others o I don’t know whats in S1/T1 but the percentage of open joints is important
Author response: Our test were carried out for the HydroSTON (porous pavers) and Ecotrihex pavers (non-porous pavers, with infiltration through the gaps). The former comprised the majority of data points, see Table S1.
Reviewer Query 13: L114 according to figure 1 and literature: 10 years is a long time, and there for valuable material, I would put this in the abstract ‘long term efficiency’
Author response: In the revised manuscript the following sentences was modified with additional text in the abstract
This paper communicates the benefits of PICPs by providing evidence of field performance of their long term efficiency.
Reviewer Query 14: L133 is [14] the only reference on this? Its different than referencing ASTM (with lots of references). Can the SWIFT method always be applied? Does S1 also say something on the slope of the permeable pavement that might influence the results of SWIDT?
Author response: A relationship between SRIT and SWIFT was developed by Lucke [14]. That procedure was verified in this study. The SWIFT procedure is quick and easy to conduct as opposed to the SRIT method. Two studies (this study and Lucke [14]) show that a relationship exist. This means that in other localities a few test can be conducted to establish a relationship between SRIT and SWIFT. Thereafter tests can be conducted using SWIFT to determined PICPs infiltration performance.
Reviewer Query 15: L146 what are the ‘These rates are much greater than the heaviest rainfall intensities ever experienced in Sydney and Wollongong’ and reference?
Author response: A new reference has been added to the revised manuscript
Current Results. Sydney - Extreme Daily Rainfall for Each Year. Current Results Weather and Science Facts (2022). Viewed 8 June 2022 https://www.currentresults.com/Yearly-Weather/Australia/NSW/Sydney/extreme-annual-sydney-precipitation.php
Reviewer Query 16: Figure2, all PICP are permeable (or non permeable in the non hydroston 80 nd 50)? And all bricks have the same size? Is the number of bricks or m2 is better to compare? Data of Lucke was impermeable l178
Author response: Author response: Size of pavers can make a difference. Note however that for non-porous pavers the perimeter is more suited than area, the later suited to porous pavers. So it is not true that area (m2) is better. Also note the size of pavers are not greatly different and not surprising given the construction requirements to install these pavers.
The relationship between SRIT and SWIFT was developed by Lucke [14]. That procedure was verified in this study. The SWIFT procedure is quick and easy to do as opposed to the SRIT method. The simplicity of the SWIFT infiltration capacity test, including the simple procedure of counting bricks, is its strength. In applying this test at other localities a few test can be conducted to establish a relationship between SRIT and SWIFT. Thereafter tests can be conducted using SWIFT to determined PICPs infiltration performance.
Reviewer Query 17: L153 again missing table
Author response: In the revised manuscript, the relevant table is now labelled as Table S1. Table 1 in the supplementary material was relabelled Table S1.
Reviewer Query 18: L157 ‘2000 mm/h (Medium Blocked) and zero where less than 30 mm/h (Fully Blocked).
What is the reference to this? Who decided what is blocked? o Table 1 at l161 : lucke et al 2015 = [14] right? Check references
Author response: In the revised manuscript, the relevant table is now labelled as Table 1.
Reviewer Query 19: L165 Tests at each location were carried out without cleaning the pavement surface prior to the measurement.
Any cleaning/maintenance before the test in the lifetime of the pavement? So maybe just before the test?
Author response: The authors did not clean the pavements before the test apart from removing large debris such as leaves. We have modified the text of the revised manuscript.
Tests at each location were carried out without cleaning the pavement surface prior to the measurement apart from removing large debri such as leaves that would interfere with the testing.
Reviewer Query 20: Check references: of Lucke et al. The data of Lucke et al. [14]
Author response: The correct reference should be Lucke et al. [14]. These have been corrected.
Reviewer Query 21: L186 table is missing and cant really judge the text anymore o 1188 indeed the slope is one of the factors…
Author response: In the revised manuscript, the relevant table is now labelled as Table S1. Table 1 in the supplementary material was relabelled Table S1.
Reviewer Query 22: L187 lots of factors … lots of uncertainty on your results, this means good documentation on these factors and data (and figures) are missing. Also factors are missing you introduce l240 another one: vegetation cover which is not included in summary l187, …. L243 saturation/…
Factors that could lead to the differences in the measured infiltration rates include
the slope of pavement surface;
age of pavers;
sub-grade structure including soil
type and water table levels;
quality of construction;
operating conditions including size and type clogging materials,
vehicles and pedestrian loads;
and frequency and quality of maintenance.
vegetation cover
saturation
Author response: The summary of data related to factors of influence is given in Table S1. A full description of data is given in the study data, see data availability statement in the paper i.e.
Data Availability Statement: Data collected in this study is available at PICPS Test Data.xlsx
Vegetation cover falls into the category of clogging and saturation under subgrade structure. Saturation falls in the category sub-grade structure including soil type, and water table levels. In the revised manuscript we have now explicitly named them in those categories as follows.
…..other factors that could lead to the differences in the measured infiltration rates include the slope of pavement surface; age of pavers; sub-grade structure including soil type, its saturation and water table levels; quality of construction; operating conditions including size and type clogging materials and vegetation cover, vehicles and pedestrian loads; frequency and quality of maintenance. The following sections highlight differences in test conditions between the two sets of data
Reviewer Query 23: L202 counting bricks … size of brick is then important when reviewing several systems… m2 is better
Author response: Size of pavers can make a difference. Note however that for non-porous pavers the perimeter is more suited than area, the later suited to porous pavers. So it is not true that area (m2) is better. Also note the size of pavers are more or less similar and not surprising given the construction requirements to install these pavers.
The relationship between SRIT and SWIFT was developed by Lucke [14]. That procedure was verified in this study. The SWIFT procedure is quick and easy to do as opposed to the SRIT method. The simplicity of this infiltration capacity test, including the simple procedure of counting bricks, is its strength. In applying this test at other localities a few test can be conducted to establish a relationship between SRIT and SWIFT. Thereafter tests can be conducted using SWIFT to determined PICPs infiltration performance.
Reviewer Query 24: L212 slope… table 1?
Author response: In the revised manuscript, the relevant table is now labelled as Table S1. Table 1 in the supplementary material was relabelled Table S1.
Reviewer Query 25: L242 … table S! figure… you lost me
Author response: In the revised manuscript, the relevant table is now labelled as Table S1. Table 1 in the supplementary material was relabelled Table S1.
Reviewer Query 26: L252 we might have a different view on ‘large’
Author response: The gaps opened up under vehicular loads are to 10 mm. The text in the revised manuscript was modifies as follows.
It was observed there were large gaps of upto 10 mm between pavers, which could have been caused by vehicular loads. These may have contributed to the variation in results.
Reviewer Query 27: Figure 3: still think its more a product review than a statement of PICIPs in general
Author response: In this study we tested at field sites we had access to. In Sydney the type of pavement installed were Ecotrihex and HydroSTON. So it not unusual that in examining the infiltration rates of PICPS installed in the field in Sydney, the characteristics of the paver are highlighted. The actual purpose of the field tests is to gauge the long term in-situ performance of PICPs and examine the results for its implications for design. There is a perception that PICPS quickly lose their infiltration capacity and this has held back their widespread application. The results of this study will challenge widely held notions and inform regulatory authorities and designers of the actual situation.
Reviewer Query 28: L275: figure 1? After figure 3? Figure 1 is at l104
Author response: L275 refers to Figure 4 i.e.
“Figure 4 shows a plot of infiltration rates against the age of PICPs”
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
I am satisfied with the answers given from review round 1, but still find (minor) errors that should not have been in a revised document. Please go through the paper line by line and correct errors as:
· Figure 1. Surface infiltration rate versus age of PICPs (non-porous), as recorded in various past studies. (Collin et al. [6], 70 Drake et al. [7], Boogaard et al. [10], Borgwardt et al. [11], Cipolla et al. [12], Sañudo-Fontaneda et al. [13] and) … and what?
· Boogaard et al. [10], and in reference Boogard
· Line 72: boogaard and lucke did 16 fieldtests not 13
· l76 Better remove the sentence ‘If plotted on Figure 1 the data would all virtually lie on the x axis given the scale of the y axis ‘ you could also use log scale at y-as and do plot all data
· L 243 but photos in their 243 paper show their sites to be relatively open: ‘sites in this study’
· Table 2: I would still explain your definition of blockage criteria: medium, partially unblocked in the table, since you cant refer to standards
· L335 reference not found
· Figure 8 parts are not visual, this is not acceptable
· L381 next to Razzaghmanesh 381 & Beecham [26] and Borgwardt [11], also ref 17 found the effect of saturation with factors even over 50% (since this is the main conclusion, back it up with literature you referenced to and hope you read it…)
· Data Availability Statement: Data collected in this study is available at PICPS Test Data.xlsx, not available for everyone
Author Response
Reviewer 1
I am satisfied with the answers given from review round 1, but still find (minor) errors that should not have been in a revised document. Please go through the paper line by line and correct errors as:
Query: Figure 1. Surface infiltration rate versus age of PICPs (non-porous), as recorded in various past studies. (Collin et al. [6], 70 Drake et al. [7], Boogaard et al. [10], Borgwardt et al. [11], Cipolla et al. [12], Sañudo-Fontaneda et al. [13] and) … and what?
Author response: The sentence was corrected.
Query: Boogaard et al. [10], and in reference Boogard.
Author response: The spelling was corrected
Query: Line 72: boogaard and lucke did 16 fieldtests not 13.
Author response: The sentence was corrected.
Query: l76 Better remove the sentence ‘If plotted on Figure 1 the data would all virtually lie on the x axis given the scale of the y axis ‘ you could also use log scale at y-as and do plot all data.
Author response: The sentence was removed.
Query: L 243 but photos in their 243 paper show their sites to be relatively open: ‘sites in this study’.
Author response: The sentence was changed to “but photos in the paper show sites to be relatively open,”
Query: Table 2: I would still explain your definition of blockage criteria: medium, partially unblocked in the table, since you cant refer to standards.
Author response: Blockage criteria was defined in Table 1 and follows Lucke et al [14]. We have added this note to Table 2 i.e. “* see Table 1 for blockage criteria. “
Query: L335 reference not found.
Author response: There is no reference for this classification. It was one adopted in this study to classify the steepness of the pavement. It was carried out by eye.
Query: Figure 8 parts are not visual, this is not acceptable.
Author response: We have reviewed Figure 8. All parts appear unblocked and clearly visual.
Query: L381 next to Razzaghmanesh 381 & Beecham [26] and Borgwardt [11], also ref 17 found the effect of saturation with factors even over 50% (since this is the main conclusion, back it up with literature you referenced to and hope you read it…)
Author response: The reference was added to the sentence
Query: Data Availability Statement: Data collected in this study is available at PICPS Test Data.xlsx, not available for everyone
Author response: We have checked the settings. It is available to all who have the link. The hyper-link is embedded in the words “PICPS Test Data.xlsx”
Author Response File: 
Author Response.docx
Reviewer 2 Report
The authors made great improvements for this manuscript. However, there are still some minor errors in this manuscript, such as:
From lines 101 to line 120, the structure and logic relationship need to be improve.
line 271, upto?
line291, the expressions related to the following figure?
line 299, Figure1?
line 335, the reference?
line 370, the expression ‘The results are shown in’?
line374 and line375, Figure 8?
line 534, Figure 2?
line 440, the reasons and explanations should be revised. ‘The later was a measurement obtained in this study.’ was not the appropriate expression.
Author Response
Reviewer 2
Query: From lines 101 to line 120, the structure and logic relationship need to be improve.
Author response: The relevant paragraphs were rewritten to improve the structure and the logical flow.
Query: line 271, upto?
Author response: We have reviewed the sentence and cannot see the error. Perhaps the reviewer can elaborate and give more details.
Query: line291, the expressions related to the following figure?
Author response: We are not clear of what the reviewer is referring to. However we have changed the sentence to the following
“Figure 4 shows a plot of infiltration rates against the age of PICPs. The overall trend of data shown in Figure 4 is depicted by the line.”
Query: line 299, Figure1?
Author response: We are not clear of what the reviewer is referring to. However we have changed the caption to the following
“Figure 4. Infiltration rate versus age of pavement for all field measurements conducted in this study.”
Query: line 335, the reference?
Author response: There is no reference for this classification. It was one adopted in this study to classify the steepness of the pavement. The classification was carried out by eye.
Query: line 370, the expression ‘The results are shown in’?
Author response: The sentence was removed and combined with the next sentence i.e.
“Figure 8 shows that at all locations, the infiltration rate decreases with each repetition of the SRIT test”.
Query: line374 and line375, Figure 8?
Author response: Reference to Figure 8 was added to the sentence.
Query: line 534, Figure 2?
Author response: Perhaps the reviewer mistyped the line number. Assuming it could be L 334, we have reviewed the sentence and cannot see the error.
Query: line 440, the reasons and explanations should be revised. ‘The later was a measurement obtained in this study.’ was not the appropriate expression.
Author response: The spelling for latter was corrected.
Author Response File: Author Response.docx
