Investigation of Some Property Changes of Light-Colored Turkish Natural Stones after High-Temperature Treatments
Round 1
Reviewer 1 Report
The authors analyzed and discussed the physical and mechanical properties of natural stones after high temperature treatment. However, there are still some problems in the current research content.
1. The authors did not perform a detailed analysis of the data in Tables 2, 3, 4 and 5, however this section is very important. I strongly recommend that the author adds the reasonable explanation.
2. XRF and XRD experiments etc. did not give detailed information about the samples. The XRD experiments were used to analyze the types of minerals in the samples, but the methods of analysis were not described in detail. In addition, the results of the XRD experiments of the samples do not seem to be of any meaningful help to the study.
3. This paper is more like a research paper, and the authors do not characterize the physical-mechanical response of natural stone after high-temperature treatment in a detailed and reasonable analysis and discussion.
4. The idea of the paper is relatively confused. For example, there are two tables 2 in the paper, but in fact they are completely independent.
Author Response
Response to Reviewer 1 Comments
Point 1. The authors did not perform a detailed analysis of the data in Tables 2, 3, 4 and 5, however this section is very important. I strongly recommend that the author adds the reasonable explanation.
Response 1. Explanations about Table 2 are in different sections of the article. For example; Line 366-374; Line 466-467; Line 476-478. Table 3 was canceled and XRD graphics were added. Please see 276. Actually, Table 4-5 has been re-presented as Figure 5-9 for easier understanding. Please see Line 307-325; Line 330-347; Line 350-367; Line 378-405.
Point 2. XRF and XRD experiments etc. did not give detailed information about the samples. The XRD experiments were used to analyze the types of minerals in the samples, but the methods of analysis were not described in detail. In addition, the results of the XRD experiments of the samples do not seem to be of any meaningful help to the study.
Response 2. All studied rocks are of sedimentary origin and contain CaCO3. This showed that exposing all natural stones (with CaCO3 content) used in the experimental study to such high temperatures may be inconvenient. The main reason for this, elements and compounds in organic group such as C, H2, N2, S2 and inorganic group such as CaCO3, CaSO4, Ca (OH)2 undergo chemical change during fire, causing molecular structure of material to deteriorate. Especially this phenomenon can be encountered in some natural stone structures containing fossils. During degradation of molecular structure of material, some harmful gases such as CO2, CO, SO2 and SO3 may occur, these gases leave body of material and create chemical deformation. This change may differ according to mineral components forming natural stone [49-51]. Similar results were obtained in this study. Please see Line 365-374. The useful contributions related to XRF are; As temperature increased, surface redness value (a*) of all samples decreased at varying rates, and this value of HO sample decreased to a minimal level compared to the others. It is thought that fluctuation in the redness value of HO sample may be due to Fe2O3 content. A similar situation is observed in WO sample. However, the fluctuation is more in HO sample with high Fe2O3 content. Please see Line 474-478. In fact, the LOI from XRF analysis directly supports these study results. Please see Line 465-466.
Point 3. This paper is more like a research paper, and the authors do not characterize the physical-mechanical response of natural stone after high-temperature treatment in a detailed and reasonable analysis and discussion.
Response 3. The results section has been reworked. Please see Line 454-455; Line 466; Line 468-470; Line 476-480. In addition, 12 new references have been added and the work has been moved to a better position. So thank you for your contribution
Point 4. The idea of the paper is relatively confused. For example, there are two tables 2 in the paper, but in fact they are completely independent.
Response 4. The importance of this study is that it contributes to limited literature on color and gloss changes of natural stones after high temperature. Especially, in the restoration of historical buildings after fire, in addition to physico-mechanical properties, changes in color and gloss should be taken into account. Therefore, it is considered in two parameters.
Author Response File: 
Author Response.docx
Reviewer 2 Report
My comments for improvement
Table 1 if possible give geolocation latitude and longitude of that places
Line 24 and fig 9 mismatches please check
fig 2 (e) samples being exposed to temperature is correct sentence
fig 2: What is capacity of point load device?
Line 105: Tian et al., (2014) were experimentally - Tian ... experimentally is correct sentence, like this few grammar issues may be corrected.
Line 112: Repeated statement - " physical, mechanical, color and gloss" is gloss and color not physical nature?
Line 115: hardness, point load strength, color and gloss- why this parameters were selected, is it based upon any literature or authors experience or code provision?
Line 124: why only sedimentary rocks selected?
Line 127: Why this size? Is it as per some code provisions, standard sizes are there in various codes, please explain.
Line 142:"were determined and compared with values" with which values this are compared?
Line 145:"The purpose of choosing different temperature values is to clearly see changes occurring in each temperature range" obviously every stone have one temperature value above which its minerals break down, this is well known fact, what is real science behind this?
Line 147: What measurements could not be taken at that temperature?
Line 160: "water absorption, porosity, 160 color, gloss," are they all NDT? under which code or literature? or authors assumption?
Line 161: if UPV atleast was done it might have shown what happened inside the rock, all tests mentioned here are surface bound tests which invalidates the results technically.
I suggest authors to read this paper"Temperature Threshold of Sedimentary Rocks: A Comparative Study | ISRM EUROCK | OnePetro"
Line 171: " Schmidt hammer hardness of rock" what is the capacity of Schmidt hammer and what is the compressive strength of rock used, if author compares this he can understand how much science is needed to interpret, I am seeing lot of poor science in this test particularly.
Line 172: What is the importance of color unless this rocks are in exposed surface of a building? In that case, if this rocks are for ornamental purpose obviously studying their strength is not necessary since they wont be loaded much in any structure, ex: Stones used for cladding.
Line 196: Why a rock is tested under point load is seriously not clear to me, it should be compressive strength test or atleast flexure, but point load test is something peculiar, surely authors might have validation for that, kindly explain in detail in one paragraph.
Line 226 onwards:800 oC: use degree symbol properly. 800o
Table 2 and 3 are important invention in this work, please interpret that properly and explain.
Can you please convert table 4 and 5 as graph since table is hard to interpret, please do this. You may even draw multiple y graphs.
Serious language issues exists everywhere in the article one example is :Many researchers were determined: Line 269: Like this so many places are there which gives confusion, author should mandatorily check and remove this before submission Ex: Line 390:" It was determined "
Fig 4,5,6,7 are repetition of previous table values, it wont add much value to article, think .
Again table 3 and fig 8 is same condition, please check
Section 4 and 5 lags connectivity, please see last figure of section 4 it ends abruptly without any interpretation leaving reader to interpret by seeing the images.
Conclusion should point what value for which rock, think and rewrite.
Authors are requested to perform the corrections and resubmit for evaluation please.
Author Response
Response to Reviewer 2 Comments
Point 1. Table 1 if possible give geolocation latitude and longitude of that places
Response 1. These samples were collected by the Alacakaya Marble Factory in Elazig (Turkey). Unfortunately, we don't have the quarry coordinates.
Point 2. Line 24 and fig 9 mismatches please check
Response 2. Actually, there is no incompatibility. Maximum darkness was obtained for all samples at 400 oC. However, the brightness (gloss) always decreased with the increase in temperature.
Point 3. fig 2 (e) samples being exposed to temperature is correct sentence
Response 3. Fig 2 (e) has been corrected. Thank you. Please see Line 146.
Point 4. fig 2: What is capacity of point load device?
Response 4. UTR-0580 Digital Point Load Tester has a 60 kN capacity test body and digital readout unit loaded with a hydraulic hand pump. Please see Line 231.
Point 5. Line 105: Tian et al., (2014) were experimentally - Tian ... experimentally is correct sentence, like this few grammar issues may be corrected.
Response 5. The article has been revised. Thank you for your interest. Please see Line 108.
Point 6. Line 112: Repeated statement - " physical, mechanical, color and gloss" is gloss and color not physical nature?
Response 6. Revised as changes in physico-mechanical properties. Please see Line 115.
Point 7. Line 115: hardness, point load strength, color and gloss- why this parameters were selected, is it based upon any literature or authors experience or code provision?
Response 7. Especially, non-destructive test methods such as hardness, porosity, water absorption, Schmidt hammer hardness, color and gloss were chosen. Thus, it is to predict the changes in the physico-mechanical properties of natural stones exposed to fire or high temperature. In addition, point load strength, which is the most common test method used in the estimation of both uniaxial compressive and tensile strengths of rocks, was determined. Please see Line 118.
Point 8. Line 124: why only sedimentary rocks selected?
Response 8. All selected rocks are the most preferred samples in many exterior coating projects in Turkey. In the literature studies, there are generally studies on igneous rocks. Therefore, sedimentary rocks were chosen.
Point 9. Line 127: Why this size? Is it as per some code provisions, standard sizes are there in various codes, please explain.
Response 9. Experimental study was conducted according to method recommended by ISRM 1985 [Reference 30]. For this purpose, 30x40x40 mm sized samples were prepared. Please see Line 225.
Point 10. Line 142:"were determined and compared with values" with which values this are compared?
Response 10. Samples at room temperature (ie, not exposed to any temperature) were accepted as reference samples. Then, other samples were compared with reference samples after exposure to each temperature. Please see Line 149.
Point 11. Line 145:"The purpose of choosing different temperature values is to clearly see changes occurring in each temperature range" obviously every stone have one temperature value above which its minerals break down, this is well known fact, what is real science behind this?
Response 11. The aim of this study is to relate the changes in physico-mechanical properties of historical buildings or structures using natural stone cladding when exposed to possible fire and high temperature (200 or 400 or 600 oC?). Thus, reinforcement can be made in accordance with the strength loss of the structure to be restored. In addition, the biggest advantage of color determination is that it gives information about the temperature the natural stone is exposed to during fire. Please see Line 476.
Point 12. Line 147: What measurements could not be taken at that temperature?
Response 12. Sedimentary samples exposed to high temperatures (such as 200, 400, 600, 800 oC) were left to cool in the oven (to avoid sudden shock). Then, experimental studies were carried out. Please see Line 162.
Point 13. Line 160: "water absorption, porosity, 160 color, gloss," are they all NDT? under which code or literature? or authors assumption?
Response 13. Non-destructive testing (Non Destructive Testing) is the method used to detect the discontinuities that cannot be detected visually in the surface or internal structure of the material without damaging the material. Therefore, except for the point load strength test, the others are considered as non-destructive testing methods.
Point 14. Line 161: if UPV atleast was done it might have shown what happened inside the rock, all tests mentioned here are surface bound tests which invalidates the results technically.
Response 14. The UPV tester is in the repair phase as a calibration error has occurred. Therefore, UPV measurements were not performed. However, in our new studies, we will deal with the internal changes of rocks, especially using UPV. Thanks for your interest and suggestion.
Point 15. I suggest authors to read this paper"Temperature Threshold of Sedimentary Rocks: A Comparative Study | ISRM EUROCK | OnePetro"
Response 15. Thank you for your very useful and helpful advice. Please see Reference 43.
Point 16. Line 171: " Schmidt hammer hardness of rock" what is the capacity of Schmidt hammer and what is the compressive strength of rock used, if author compares this he can understand how much science is needed to interpret, I am seeing lot of poor science in this test particularly.
Response 16. Schmidt hammer hardness is a very important parameter in investigation of high temperature effect on natural stones, since it is a non-destructive test and is used to predict mechanical strength of rocks. In this study, it contributes to evaluation of mechanical strength of natural stone as a result of a possible fire (high temperature) using non-destructive testing method of Schmidt hardness hammer. The formation of new micro-macro crack, fracture and distortion with the increase in temperature negatively affected Schmidt hammer hardness values of rocks. Many researchers have obtained strong relationships between mechanical properties and Schmidt hammer hardness as a result of experimental and statistical studies. In this case, when considering strong relationship between Schmidt hammer hardness and mechanical properties (uniaxial compression, impact, bending strength, etc.), it is obvious that such a high loss cannot be ignored. Please see Line 340-347.
Point 17. Line 172: What is the importance of color unless this rocks are in exposed surface of a building? In that case, if this rocks are for ornamental purpose obviously studying their strength is not necessary since they wont be loaded much in any structure, ex: Stones used for cladding.
Response 17. Yes, this study will actually benefit both of them. Because not only the color and physical properties were considered, but also the point load strength value was determined. Point load strength is the most common test used to estimate both compressive and tensile strength of rocks.
Point 18. Line 196: Why a rock is tested under point load is seriously not clear to me, it should be compressive strength test or atleast flexure, but point load test is something peculiar, surely authors might have validation for that, kindly explain in detail in one paragraph.
Response 18. Uniaxial compressive strength of rocks is the most preferred mechanical test in earth science projects such as mining and civil engineering. This test requires time consuming, expensive equipment, uniformly geometrically shaped specimens and skilled personnel. However, in some situations where time is limited and sufficient samples cannot be obtained, it is easier to use the point load strength suggested by ISRM (1985). Therefore, there is increasing interest in point load strength tests that are portable, inexpensive, fast, and can be used in both field and laboratory conditions. The point load strength index is used to indirectly determine other strength parameters such as uniaxial compression and tensile strength. Please see Line 221-228.
Point 19. Line 226 onwards:800 oC: use degree symbol properly. 800o
Response 19. Thanks for your attention. Please see Line 260.
Point 20. Table 2 and 3 are important invention in this work, please interpret that properly and explain.
Response 20. Table 3 was canceled and XRD graphics were added. Explanations about Table 2 are in different sections of the article. For example; Line 366-374; Line 466-467; Line 476-478.
Point 21. Can you please convert table 4 and 5 as graph since table is hard to interpret, please do this. You may even draw multiple y graphs.
Response 21. Some reviews wanted it to be shown as a table and the standard deviation added. The table has been updated again.
Point 22. Serious language issues exists everywhere in the article one example is : Many researchers were determined: Line 269: Like this so many places are there which gives confusion, author should mandatorily check and remove this before submission Ex: Line 390:" It was determined "
Response 22. Thanks for your attention. The whole of paper has been revised.
Point 23. Fig 4,5,6,7 are repetition of previous table values, it wont add much value to article, think . Again table 3 and fig 8 is same condition, please check
Response 23. Some reviews wanted it to be shown as a table and a graphical representation of the percentage changes.
Point 24. Section 4 and 5 lags connectivity, please see last figure of section 4 it ends abruptly without any interpretation leaving reader to interpret by seeing the images.
Response 24. A new paragraph has been added. Please see Line 435-443
Point 25. Conclusion should point what value for which rock, think and rewrite.
Response 25. The results section has been reworked. Please see Line 454-455; Line 466; Line 468-470; Line 476-480.
Reviewer 3 Report
In this article, the properties of 5 types of stones were studied after exposure for 120 minutes at various temperatures.
This work is more consistent with the communication than the article, since the literature review is quite short (less than 40 sources for whole work) and there is no discussion of the results.
The work may be interesting for publication if it is reworked. Here are some remarks:
1. The list of keywords does not reflect the essence of the article. I believe that objects or research methods would improve the representativeness of keywords. I would also recommend reworking the titlte.
2. Section 2.2.3 needs a new design. Formulas should be centered, formula numbers should be aligned.
3. The annotation states that water absorption, porosity, hardness, strength under point load, color and gloss have been studied in the work. I recommend highlighting these methods separately in section 2.2. Moreover, each method, device, methodology should be described, indicating the country and characteristics of the device so that the data can be reproduced. The measurement error should be specified too.
4. I believe that the first 3 sentences in the abstract should be reworked 6 or combined into one, since they are more suitable for introduction.
5. Table 3 is not displayed correctly, it should be reworked.
6. I believe that measurement errors should be displayed on the graphs or indicated (Figures 4,5,6,7,8).
7. In my opinion, section 4 should be reworked. The paper presents the results of experimental work, however, it is important to indicate the alleged causes and consequences. What caused the changes?
Author Response
Response to Reviewer 3 Comments
Point. 1. The list of keywords does not reflect the essence of the article. I believe that objects or research methods would improve the representativeness of keywords. I would also recommend reworking the titlte.
Response 1. Title changed. New keywords added. Please see Line 1-25.
Point 2. Section 2.2.3 needs a new design. Formulas should be centered, formula numbers should be aligned.
Response 2. 2.2.3 has been redesigned. Please see 220-228. Formulas were written as 'Palatino Linotype-10 point'.
Point 3. The annotation states that water absorption, porosity, hardness, strength under point load, color and gloss have been studied in the work. I recommend highlighting these methods separately in section 2.2. Moreover, each method, device, methodology should be described, indicating the country and characteristics of the device so that the data can be reproduced. The measurement error should be specified too.
Response 3. Non-destructive tests (water absorption, porosity, color, gloss, Schmidt hammer hard-ness) were handled separately. Please see Line 171-188. Specific information about the devices used in each experiment was given. Please see Line 202-203; Line 214-216; Line 230-232
Point 4. I believe that the first 3 sentences in the abstract should be reworked 6 or combined into one, since they are more suitable for introduction.
Response 4. Thanks for your contribution. Please see second paragraph of Introduction
Point 5. Table 3 is not displayed correctly, it should be reworked.
Response 5. Table 3 was canceled and XRD graphics were added. Please see 276.
Point 6. I believe that measurement errors should be displayed on the graphs or indicated (Figures 4,5,6,7,8).
Response 6. Standard deviations have been added. Please see 286-287.
Point 7. In my opinion, section 4 should be reworked. The paper presents the results of experimental work, however, it is important to indicate the alleged causes and consequences. What caused the changes?
Response 7. This study was reinforced by 12 new references. A new paragraph has been added. Please see Line 435-443. Please see Line 366-374 The results section has been reworked. Please see Line 454-455; Line 466; Line 468-470; Line 476-480.
Author Response File: Author Response.docx
Reviewer 4 Report
Dear Authors,
As the reviewer, I would like to thank you for the possibility of so nice and logically-composed paper. I don't have very serious remarks on submitted paper, but I have some points, which can improve the quality of whole text:
1) ALL applied devices should be mentioned in text (producer, model and producer's country) - even XRF / XRD devices;
2) Authors should decide which samples dimensions were applied (line 127 vs line 163);
3) Results dispersion should be included in figures. It would be desirable to add appendix with tables containing all experimental results with mean values and standard deviation. It is important especially due to non-homogenity of material. Moreover in this appendix figures with XRD patterns could be inserted ;
4) line 274 - remove full stop (dot) after "figure";
Kind regards
Author Response
Response to Reviewer 4 Comments
Point 1. ALL applied devices should be mentioned in text (producer, model and producer's country) - even XRF / XRD devices;
Response 1. Specific information about the devices used in each experiment was given. Please see Line 202-203; Line 214-216; Line 230-232. XRD and XRF analyzes were performed in a private institution.
Point 2. Authors should decide which samples dimensions were applied (line 127 vs line 163);
Response 2. Block samples of 30*40*40 mm dimensions were used for point load strength test, color and gloss. For Schmidt hammer hardness, water absorption and porosity of rocks 70x70x70 mm were used.
Point 3. Results dispersion should be included in figures. It would be desirable to add appendix with tables containing all experimental results with mean values and standard deviation. It is important especially due to non-homogenity of material. Moreover in this appendix figures with XRD patterns could be inserted ;
Response 3. Standard deviations have been added. Please see 286-287.
Table 3 was canceled and XRD graphics were added. Please see 276.
Point 4. line 274 - remove full stop (dot) after "figure";
Response 4. Removed 'dot' after Figure. Thanks for your attention.
Author Response File: Author Response.docx
Round 2
Reviewer 2 Report
Dear Author,
I had recommend the article for inclusion in the present form
RG
Reviewer 4 Report
Thank you for cooperation.
Best regards
Reviewer
This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.
