Assessment of the Compression Properties of Different Giant Bamboo Species for Sustainable Construction
Round 1
Reviewer 1 Report
Journal: MDPI
Title: Assessment of the Compression Properties of Different Giant 2 Bamboo Species for Sustainable Construction
The authors have presented the mechanical properties of bamboo from different species regarding its use as a construction material. The compression properties of bamboo species from different continents were investigated. The authors attempted to justify the compressive behaviours of various bamboo tribes that could show satisfactory performance in construction, which would be sustainable and environmentally friendly construction materials worldwide.
However, it still needs some minor clarification to make it publishable as scientific research. The concerns are presented as follows:
Key comments
1. In the introduction section, the authors have briefly explained the previous studies regarding the issues. It is suggested to add such relevant properties (if available), though limited of past data considering the topics, which would be the evidence for novelty.
2. Chapter two: (Material)- Since the detail specimens are illustrated in table, So, try to compact description with key information [line 192-205].
3. Chapter two: (Method)- the authors stated that “The vertical load and displacement were automatically recorded by a computerized system at 1-second intervals”. However, the instruments that conveyed the deformation data were not mentioned, and it needed to be displayed in the test setup image. It is also recommended to include instructions on recording the deformation during the test.
4. Chapter two: (Method)- As the section is hollow, it is suggested to elaborate on calculating the cross-section area, stress, and modulus of elasticity (Ex). So, the reader can get it easily.
5. The authors have illustrated experimental results (3.1 and 3.2) with sufficient graphical and numerical information. Because of this, it is suggested that the text passage be short instead of long, and that the results be linked to data and graphs, taking into account the purpose of the research. So, the reader can get it easily.
6. Chapter 3 (result; table 2.), provide information regarding the “Ec”.
7. Though the topics is concerned on the compression properties, the readers could get more information if the authors provided the behaviors of such materials considering the stiffness and slenderness (because of its narrow section)
8. Chapter four (4.2): It is advised to illustrate only factual information, like in 4.1; the detailed explanation is already mentioned in Chapter 3.
9. Chapter four (4.3): Is it reliable to use as a structural member, or what types of construction materials would be in construction? “Only compressive strength decides whether to use or not as construction materials? Provide concrete justification for reliability to use in construction.
10. The conclusion seems tilt to generic, so the authors should present a concrete conclusion rather than a generic one.
11. There are minor typos in the manuscript; checking the typos and grammatical odds thoroughly is suggested.
Author Response
The authors gratefully appreciate the reviewer for the comprehensive review of the manuscript and valuable comments. The authors went through the comments and addressed the concerns as can be found in the below lines:
- In the introduction section, the authors have briefly explained the previous studies regarding the issues. It is suggested to add such relevant properties (if available), though limited of past data considering the topics, which would be the evidence for novelty.
Thank you very much for this valid comment. As mentioned by the reviewer, the existing test data on the mechanical properties of giant bamboo species are limited. The authors included the results from existing studies in the revised manuscript with track changes between lines 104 to 120.
- Chapter two: (Material)- Since the detail specimens are illustrated in table, So, try to compact description with key information [line 192-205].
Done. Line 194, the figure caption is now more compact so the reader can find the needed details in Table 1.
- Chapter two: (Method)- the authors stated that “The vertical load and displacement were automatically recorded by a computerized system at 1-second intervals”. However, the instruments that conveyed the deformation data were not mentioned, and it needed to be displayed in the test setup image. It is also recommended to include instructions on recording the deformation during the test.
The measurement of displacements and the applied load were conducted by embedded instruments within the state-of-the-art universal testing machine that can perform uniaxial testing by reading accurate stress and strain results that ensure minimal specimen out-of-straightness under the load. The displacement measurement accuracy of the machine is ±0.01 mm. This has been made clear to the readers in line 229.
- Chapter two: (Method)- As the section is hollow, it is suggested to elaborate on calculating the cross-section area, stress, and modulus of elasticity (Ex). So, the reader can get it easily.
This is a very important comment. The cross-sectional dimensions of the bamboo specimens were measured to the precision of 0.1 mm. It should be pointed out that where samples obtained a variation in cross-sectional diameters, 6 measurements were taken, three at the top and three at the bottom. The mean of these measurements was used. The aim of this approach was to better account for the natural variations in the bamboo’s anatomy. These lines can be found in manuscript lines 204- 207. The average stress in the cross-section is calculated by dividing the applied force by the average area of the cross-section (lines 366-368). The modulus of elasticity was calculated using the following equation (1) which is provided by ISO-22157 (2019).
The equation calculates the secant modulus of elasticity between the points corresponding to the applied load and compressive strain of 60% and 20% of failure. In this manner, F60 and F20 are the applied load at 60% and 20% of the load at peak, correspondingly. Whereas e60 and e20 are the compressive strain corresponding to 60% and 20% of the load at peak, respectively. These lines can be seen in lines 248-256.
- The authors have illustrated experimental results (3.1 and 3.2) with sufficient graphical and numerical information. Because of this, it is suggested that the text passage be short instead of long, and that the results be linked to data and graphs, taking into account the purpose of the research. So, the reader can get it easily.
Thank you very much for your positive feedback on the extent of the presentation of the results. The point of the reviewer is well-taken and it's quite valid. More references to the graphs and tables has been provided in the text now.
However, considering the broad types of the readers of Sustainability Journal, we decided to provide detailed interpretations of the graphs and numerical details for the readers who prefer to find such data through a narrative in the text form. In this manner, we will make sure a broader audience can benefit from the results of this study.
- Chapter 3 (result; table 2.), provide information regarding the “Ec”.
Excellent point. A new sub-section is now been added as 4.3. Modulus of Elasticity in Compression.
- Though the topics is concerned on the compression properties, the readers could get more information if the authors provided the behaviors of such materials considering the stiffness and slenderness (because of its narrow section)
Compression testing on ISO 22157:2019 standard is designed in a way to lead to a pure compressive failure to avoid buckling as much as possible. In order to look into local buckling failure possibilities due to the hollow shape of the bamboo specimens, bamboo species from the same species are needed with the test parameter being the diameter to the wall thickness and height etc. With the current selection of bamboo specimens from different species, no solid conclusions can be drawn. In fact, such a conclusion was not in the scope of this study. However, this will be covered in our future investigations. We appreciate this interesting point mentioned by the reviewer.
- Chapter four (4.2): It is advised to illustrate only factual information, like in 4.1; the detailed explanation is already mentioned in Chapter 3.
Done.
- Chapter four (4.3): Is it reliable to use as a structural member, or what types of construction materials would be in construction? “Only compressive strength decides whether to use or not as construction materials? Provide concrete justification for reliability to use in construction.
That's a valid point. Clarifications have been made in line 504 for this matter.
- The conclusion seems tilt to generic, so the authors should present a concrete conclusion rather than a generic one.
The conclusion is now revised to focus only on the straightforward and right-to-the-point achievements of the study. Thanks.
- There are minor typos in the manuscript; checking the typos and grammatical odds thoroughly is suggested.
Thanks for your careful observation. The manuscript has been reviewed professionally for any minor language errors.
Reviewer 2 Report
1. Research is focussed to compare compression properties of differents giant bamboo species, to evaluate the factibility to use as construction material. Main question: Does the giant bamboo have from different continents good compression properties to use as a material to construction?
2. Although there are many studies about compression properties of giant bamboo, this study show a novelty assessment between samples selected of different continents applying ISO 22157:2019 standard. I think that is necesary in this point include in discussion data from recent references, because only one ISO document is from 2021. The the most amount of references are from five years or more that were published.
3. This study compare compresion properties of giant bamboo selected form diferent continents. Othes researchs have taken samples form specific regions.
4. Research was focussed to compresión properties by using the ISO 22157:2019 standard. I consider adequate the methodology employed to obtain results contundents.
5. I think that the results, analysis and conclusions are coherents.
But, I consider that the discussion may be improved including comparision with data reported in more recent references.
6. References support discusion and conclusions, but the most amount of them are five or more years published. This work may be improved including recent references.
7. Figure 1 show series a), b), c) and e) at same position; series d) is in other position. Is convenient locate at same manner every samples.
Author Response
The authors would like to thank the reviewer for their thorough review and productive comments. The authors went through the comments and addressed the concerns as can be found in the below lines:
- Research is focussed to compare compression properties of differents giant bamboo species, to evaluate the factibility to use as construction material. Main question: Does the giant bamboo have from different continents good compression properties to use as a material to construction?
The chosen species from different continents have been used in rural construction for their excellent mechanical properties including compression properties. However, the compression properties of these bamboo species have not been evaluated and compared with one another in an academic study so far. We have added a line to clarify this matter in the manuscript (Lines 25-27).
- Although there are many studies about compression properties of giant bamboo, this study show a novelty assessment between samples selected of different continents applying ISO 22157:2019 standard. I think that is necesary in this point include in discussion data from recent references, because only one ISO document is from 2021. The the most amount of references are from five years or more that were published.
The reviewer is absolutely correct. The novelty of this study is that the authors were able to gather different bamboo species from different continents and test and compare the results of those bamboo testings with one another. The added lines (L25-27) indicate this point.
In terms of the use of updated ISO standards, the authors went through the history of the standardization of bamboo testing in the manuscript which goes back to 1973. For the determination of the physical and mechanical properties of bamboo culms, the latest standard is ISO 22157:2019 which we used in the study. There is no more recent standard codes for such tests at the time being. It should be noted that the ISO 22156:2021 code is for structural designs of buildings and can not be used for compressive testing.
- This study compare compresion properties of giant bamboo selected form diferent continents. Othes researchs have taken samples form specific regions.
The authors fully agree with the reviewer on this point. Proper modifications have been made in lines 136 and 138 to emphasis the novelty of this study. Thank you very much.
- Research was focussed to compresión properties by using the ISO 22157:2019 standard. I consider adequate the methodology employed to obtain results contundents.
Thank you very much for this valid comment. The methodology is provided in section 2.2 on page 6. Additional lines are included to describe the methodology more in detail.
- I think that the results, analysis and conclusions are coherents. But, I consider that the discussion may be improved including comparision with data reported in more recent references.
The authors appreciate the reviewer’s careful review of the coherence of the manuscript. Adding more data from test results from other researchers is an excellent point. To this end, the results of Brazilian Phyllostachys edulis testing and Guadua bamboo testing by other researchers were added to the discussion part on page 15.
- References support discusion and conclusions, but the most amount of them are five or more years published. This work may be improved including recent references.
This is a valid point. More updated references that are related to this study and have been conducted in recent years are now added in references no. 30 and 31.
- Figure 1 show series a), b), c) and e) at same position; series d) is in other position. Is convenient locate at same manner every samples.
Thank you very much for your careful review of the manuscript. This was also our intention to have all the species with the same angle on the photos but unfortunately, we do not have access to such uniform photos now since the photos have been taken separately by different researchers prior to the testing.
Reviewer 3 Report
Comments on 2299232
It is an interesting topic that to discuss the compression properties of different giant bamboo species for sustainable construction. Some comments are listed as follows.
1. The introduction is well-written. The following paper could be involved.
Jiang, J., Du, J., Li, H., Mei, C., & Gong, X. (2022). Hydrophobicity Improvement on Wood for a Better Application of This Bio-Based Material. Coatings, 12(10), 1465.
2. The quality of the figures should be improved.
3. The moisture content of the bamboo is important for bamboo properties, such as compression strength and dimensional stability. The MC of the bamboo for tests should be emphasized.
4. The conclusion should be simplified to make it clear.
Author Response
The authors very much appreciate the careful comments of the reviewer. The authors went through the comments carefully and addressed those according to the reviewer's concerns as follows:
It is an interesting topic that to discuss the compression properties of different giant bamboo species for sustainable construction. Some comments are listed as follows.
Thank you very much for your positive feedback.
The introduction is well-written. The following paper could be involved.
Jiang, J., Du, J., Li, H., Mei, C., & Gong, X. (2022). Hydrophobicity Improvement on Wood for a Better Application of This Bio-Based Material. Coatings, 12(10), 1465.
The authors thank the reviewer for introducing this valuable reference. This reference is now added to the manuscript as reference 2.
The quality of the figures should be improved.
The figures' quality is now improved using more high-definition adoption of figures in the new revision.
The moisture content of the bamboo is important for bamboo properties, such as compression strength and dimensional stability. The MC of the bamboo for tests should be emphasized.
The authors agree with the reviewer that the moisture content has an essential influence on the mechanical property of the reported bamboo specimens. The average moisture content which was 15.8% is now added to the manuscript.
The conclusion should be simplified to make it clear.
The conclusion is now more straightforward and up to the point.
Reviewer 4 Report
The paper presents the compressive test results of giant bamboo species. The study is not mew, but the test results are meaningful to enrich the database of bamboo properties.
Author Response
The authors would like to thank the reviewer for their comments. As mentioned correctly by the reviewer, studies on the compressive strength of giant bamboo species are not considered new, however, the novelty of this study is on gathering different giant bamboo species from different continents for mechanical properties assessments, which is unprecedented to the best of our knowledge. In addition, the results of this study will add to the existing database of test results on compression testing of giant bamboo species suitable for construction, as rightly mentioned by the reviewer.
